Chrome拡張機能のレビュー・比較・プライバシー監査

Image Converter · ハウツー · 画像Chrome で WebP を PNG に変換する方法画像を右クリックしてローカルコンバーターを使うか、Canvas 上で動作するブラウザベースのツールにファイルをドロップします。アップロードもアカウントも不要です。最速の方法と、まとめて処理する方法を紹介します。

NetworkRules · 比較 · ネットワークNetworkRules と Requestly：どちらのネットワークルールツールが合う？Requestly はチーム同期とログインを備えたクラウド製品。NetworkRules はローカルファーストで、アカウント任意、テレメトリゼロです。クラウド同期のチームワークスペースには Requestly を、アカウントなしでクリーンなローカルルールが欲しいなら NetworkRules を選びましょう。

Word Counter · How-to · WritingHow to count words on any web page in ChromeSelect the text on the page, then open Word Counter — it shows words, characters, sentences and reading time instantly, computed locally. No pasting into another website.

Dev Toolbox · How-to · DeveloperHow to get and read a JWT in Google ChromeFind the token in an Authorization: Bearer header, localStorage or a cookie, then paste it into DevKit's JWT tab — it decodes the header, payload and expiry locally, with nothing uploaded and the signature never transmitted.

NetworkRules · How-to · DeveloperHow to mock API responses in ChromeAdd a rule with a URL pattern, method and status code, then paste the JSON you want returned — the extension intercepts matching requests and returns your response locally, with no proxy or server.

DozeKeep · How-to · PerformanceHow to suspend inactive Chrome tabs to save memoryLet idle tabs go to sleep after a set time — the extension frees up to 90–95% of each tab’s memory and shows a lightweight placeholder. Click the tab to wake it exactly where you left off. Keep pinned, audible, or allowlisted sites always awake.

ReproKit · ハウツー · 開発者Chrome でコンソールとネットワークログ付きのバグレポートを記録する方法録画を押してバグを再現し、停止するだけ——拡張機能が画面・コンソール・ネットワーク通信・再現手順を1つの共有可能なバンドルにまとめます。機密値は自動でマスクされ、すべてブラウザー内でローカルに作成されます。

AuthRoam · How-to · DeveloperHow to switch API auth tokens across environments in ChromeCapture the Authorization header once in DevTools, save it as an environment (dev, staging, prod), then switch the active token per environment — no re-login. Tokens are decoded and stored locally, with zero telemetry.

CiteRoam · How-to · ResearchHow to cite a web page or PDF in Chrome (APA, MLA, Chicago)Open the side panel on any page or PDF and generate a formatted citation in APA, MLA, Chicago or GB/T with one click, then keep it in a private reference library. Everything runs locally — your sources stay in the browser.

ProofJump · How-to · ResearchHow to fact-check a page or AI answer against its sources in ChromeOpen the side panel, ask about the page, and every answer cites and highlights the exact source sentence — click to jump to the evidence in the page, or see clearly when there is none. It reads only the page you’re on.

Contrast Checker · How-to · AccessibilityHow to check color contrast for WCAG in ChromeOpen Contrast Checker's popup, pick two colors or sample them from the page, and read the contrast ratio with an instant WCAG AA/AAA pass or fail. For a full audit, scan the whole page from the side panel. Everything is computed locally — no color leaves your browser.

Contrast Checker · How-to · AccessibilityWCAG AA vs AAA contrast: the ratios your colors actually needAA requires a contrast ratio of 4.5:1 for normal text and 3:1 for large text; AAA raises that to 7:1 and 4.5:1. Most products and regulations target AA. Contrast Checker grades any pair against both levels at once, locally in Chrome.

Screen Ruler · How-to · MeasurementHow to measure elements on a web page in pixelsClick the Screen Ruler icon and drag across anything on the page to read its size in pixels, or hover an element to get its rendered dimensions. The overlay only runs on the tab where you invoke it, and Esc removes it completely.

Screen Ruler · How-to · Design QAHow to check spacing and alignment on a live web pageOpen Screen Ruler on the page, hover elements to read the spacing between them in pixels, and drop guides along edges that should line up — anything misaligned misses the line. It runs only on the tab you invoke it on; Esc clears it.

Font Finder · How-to · TypographyHow to identify a font on any website in ChromeOpen Font Finder, click Inspect, then hover the text. A tooltip shows the typeface that actually rendered — plus its weight and size — computed locally in your browser. No screenshots, no upload, no DevTools digging.

Font Finder · How-to · TypographyHow to find the CSS font stack of any text on a pageStart Font Finder's inspector, hover the text, click to pin its detail card, then hit Copy CSS. You get the full font-family stack plus weight, size, line-height, letter-spacing and color as a paste-ready declaration block — built locally in your browser.

Case Converter · How-to · WritingHow to convert text to title case correctly (small words included)Paste your text into Case Converter and click Title Case. It applies the publishing convention: small words like "of", "and" and "the" stay lowercase unless they are the first or last word. Everything runs locally in the popup.

Case Converter · How-to · WebHow to create a URL slug from a titlePaste the title into Case Converter and click Slugify. You get a lowercase, hyphen-separated, ASCII-only slug — accents are transliterated (café → cafe), and the tool tells you when characters had to be dropped. All local, nothing uploaded.

Image OCR · How-to · OCRHow to extract text from an image in ChromeDrop the image into a local OCR workspace — recognition runs on a bundled Tesseract engine inside your browser, so the image is never uploaded. You get editable, selectable text back in seconds, ready to copy.

Image OCR · How-to · OCRHow to copy text from a screenshot in ChromeCapture the region of the page that contains the text — or paste an existing screenshot — and let a local OCR engine turn it into selectable text. Everything is recognized in your browser: no upload, no account, works offline.

CookieVault · How-to · PrivacyHow to auto-delete cookies except a whitelist in ChromeUse an MV3-native cleaner: set the default action to "clean on close", then whitelist the domains you trust. Cookies for everything else are deleted seconds after you close the tab — with an activity log so the cleanup is never a black box.

CookieVault · How-to · PrivacyHow to view and edit cookies in Chrome manuallyDevTools shows cookies but barely lets you change them. A dedicated cookie editor lists every cookie by domain and lets you edit any field inline — name, value, domain, path, SameSite, Secure, HttpOnly, expiry — plus import and export as JSON.

PDF to Image · How-to · PDFHow to convert a PDF to JPG without uploading itSkip the upload sites. PDF to Image is a free Chrome extension that renders each page of your PDF as a JPG or PNG entirely on your device — no upload, no sign-up, and it keeps working offline.

PDF to Image · How-to · PDFHow to combine images into one PDF in ChromeOpen PDF to Image, switch to Images → PDF, drop your JPG or PNG files, drag them into order and save — one PDF, assembled entirely on your device. No upload site, no sign-up, no printing tricks.

PDF Merge · How-to · PDFHow to merge PDF files offline in your browserPDF Merge is a free Chrome extension that combines your PDFs locally: drop the files, drag them into order and click Merge. Files are never uploaded — it works with no internet connection at all.

PDF Merge · How-to · PDFHow to split a PDF into separate filesOpen PDF Merge in Chrome, choose Split PDF, add page ranges like 13-24 and click Split — each range becomes its own file, produced entirely in your browser. Nothing is uploaded, and password-protected files are opened locally.

AuthRoam · How-to · DeveloperHow to decode a JWT and check its expiry in Chrome DevToolsOpen a DevTools panel that captures the token from a real request and decodes the header, payload and claims locally — with iat and exp rendered as readable dates and expired tokens flagged. Decoding is not verification: the signature is not checked, and the panel says so. Nothing leaves your browser.

AuthRoam · How-to · DeveloperHow to inject an Authorization header per environment in ChromeA header editor like ModHeader can attach one static Authorization header; the per-environment version is to capture each environment’s token from a real request, save it as dev/staging/prod, and switch which one is injected — with expiry visible and everything stored locally.

AuthRoam · How-to · DeveloperHow to capture API tokens from network requests in ChromeOpen a DevTools panel that watches the tab and collects every bearer token, cookie credential and JWT the page sends — badged by type and expiry, with the raw token masked until you reveal it. Capture, decoding and storage are 100% local; the token never leaves your browser.

Case Converter · How-to · WritingHow to convert text to uppercase or lowercase without retypingPaste the text into the Case Converter popup and click UPPERCASE or lowercase. Only letter case changes — spacing, punctuation and line breaks stay exactly as they were — and everything runs locally, so nothing is uploaded.

Case Converter · How-to · DevelopercamelCase vs snake_case vs kebab-case: where each belongs, and how to convertcamelCase is the JavaScript/JSON convention, snake_case belongs to Python and SQL, kebab-case to CSS classes, file names and URLs. To convert between them, paste the identifier into Case Converter and click the target style — it re-tokenizes on case and acronym boundaries, all locally.

Case Converter · How-to · WritingHow to clean up pasted text: extra spaces, blank lines and hidden charactersPaste the text into Case Converter and click Clean all. It collapses repeated spaces, trims line edges, reduces runs of blank lines to one paragraph break, strips invisible characters and soft hyphens, and straightens curly quotes — then reports exactly what it removed. All local.

CiteRoam · How-to · ResearchHow to cite a website in APA format (7th edition) in ChromeOpen the CiteRoam side panel on the page (or press Alt+C), choose APA, and it builds the reference from the page's metadata — author, date, title, site name, URL — locally with Citation.js. Check the detected fields against the page, then copy the citation or save it to your private library. No account, and nothing about the page is uploaded.

CiteRoam · How-to · ResearchHow to use a bibliography generator in Chrome — no account, no uploadsInstead of pasting URLs into a citation website, cite each source from the CiteRoam side panel as you read it. Every reference is formatted locally in APA, MLA, Chicago or Harvard and saved to a private library, so your works-cited list is ready when the paper is. Export BibTeX or RIS if you work in LaTeX or a reference manager.

CiteRoam · How-to · ResearchHow to highlight and save quotes from web pages — with the source attachedSelect the passage on the page, save it to CiteRoam's evidence library, and the quote is stored together with where it came from — ready to cite in APA, MLA, Chicago or Harvard. Everything stays in your browser: no account, no upload.

CiteRoam · How-to · ResearchHow to choose a citation manager Chrome extensionDecide first whether you need a full reference manager with a cloud library and word-processor plugin (Zotero or Mendeley with their connectors) or a lightweight in-browser citation tool. Then check four things: where your data lives, which styles it formats, whether it can capture quotes with sources, and whether it exports BibTeX/RIS so you're never locked in.

Contrast Checker · How-to · AccessibilityHow to scan a page for contrast issues in ChromeOpen Contrast Checker's side panel on the page and run a scan: it walks the visible text, computes each ratio locally, and lists every combination that fails WCAG AA or AAA. Fix the CSS, re-scan the same tab, and backgrounds it can't resolve — gradients, images — are marked unmeasurable instead of given a fake number.

Contrast Checker · How-to · AccessibilityHow to fix low contrast text on a web pageSample the failing text and background in Contrast Checker's popup, then adjust lightness — darken the text or lighten the background — until the WCAG verdict flips: 4.5:1 for normal text, 3:1 for large text. Fix the shared CSS token, re-check the rendered page, and put a scrim behind text that sits on images.

Contrast Checker · How-to · AccessibilityHow to check non-text contrast of buttons and UI componentsWCAG 1.4.11 requires 3:1 contrast for the parts of UI components you need to perceive — input borders, focus rings, meaningful icons — measured against their adjacent colors. Sample each pair with Contrast Checker's eyedropper on the live page and read the ratio: 3:1 or better passes. Button labels are text and still need 4.5:1.

CookieVault · How-to · PrivacyHow to choose a cookie editor Chrome extension you can trustA cookie editor reads your session cookies — which are your logins — so picking one is a security decision. Check four things: a minimal permission surface, open source with zero network access, a native Manifest V3 build, and full-field editing with JSON import/export. Here's the checklist, plus where our own editor stands.

CookieVault · How-to · PrivacyHow to extract cookies from Chrome as a JSON fileChrome has no export button — DevTools only shows cookies, and document.cookie can't even see HttpOnly ones. A dedicated cookie manager extracts every cookie for a site into a JSON file in one click, and imports it back on another machine or profile. Treat the file like a password: exported session cookies are live logins.

CookieVault · How-to · PrivacyHow to clear site data on tab close in ChromeDeleting cookies isn't enough — sites also persist state in localStorage, IndexedDB, Cache Storage and service workers. Set an auto-cleaner to "clean on close", enable its optional site-data switch, and each site's entire storage footprint is wiped seconds after you close its last tab — except the domains you whitelist.

Dev Toolbox · How-to · DeveloperHow to decode Base64 in Chrome (and encode it back)Copy the Base64 string, open DevKit's Base64 tab and paste it — the decoded UTF-8 text appears instantly, entirely in your browser. It tolerates base64url, missing padding and copied-in line breaks, and encodes in the other direction too. Nothing is uploaded.

Dev Toolbox · How-to · DeveloperHow to generate a UUID in Chrome (UUID generator + ULID)Open DevKit's IDs tab and a fresh UUID v4 is already waiting — copy it, regenerate, or raise the count to mint a batch. Need sortable, database-friendly ids instead? Switch to ULID. Everything is generated locally with the browser's crypto RNG; nothing is sent anywhere.

Dev Toolbox · How-to · DeveloperHow to convert a Unix timestamp to a date in ChromePaste the number into DevKit's timestamp tab: it auto-detects seconds vs milliseconds and shows ISO 8601, UTC, your local time and a relative "how long ago / until". It converts dates back to epoch seconds too — all offline, inside the popup.

Dev Toolbox · How-to · DeveloperHow to test a regex in Chrome with an offline regex testerOpen DevKit's regex tab, type the pattern, toggle flags and paste sample text — matches, capture groups and named groups update live. A runaway pattern is killed by a worker timeout instead of freezing anything, and your test text never leaves the browser.

DozeKeep · How-to · PerformanceHow to check which Chrome extensions are taking up memoryPress Shift+Esc (Windows/Linux) or open ⋮ → More tools → Task manager, then sort by Memory footprint. Rows prefixed “Extension:” are your extensions. In most browsers, though, the heavy rows turn out to be tabs — and those you can reclaim without closing anything.

DozeKeep · How-to · TabsOneTab Chrome extension: how it works, and an alternative that keeps tabs openOneTab saves memory by closing every tab into a list of links — great for archiving, but your layout, scroll positions and in-page state are gone. A tab suspender frees comparable memory while every tab stays in place. Here's the honest trade-off and how to set up the suspend-in-place workflow.

DozeKeep · How-to · RecoveryRecovering lost tabs in Chrome: shortcuts, history, and a session extensionPress Ctrl+Shift+T (⌘+Shift+T on Mac) to reopen the last closed tab — repeat it to walk further back, including whole windows. ⋮ → History → Recently closed restores crashed windows in one click. For the cases those miss, a session-snapshot extension keeps its own restorable copy.

DozeKeep · How-to · TabsHow to save tabs in Chrome — bookmarks, tab groups, or a session extensionFor a quick save, Ctrl+Shift+D bookmarks every tab in the window into a folder. For a workspace you'll return to, save a session snapshot instead — it keeps windows, tab order and pinned state, and restores in one click. And if the real problem is memory, suspend the tabs rather than closing them.

Font Finder · How-to · TypographyWhat font does a website use? Three ways to check in ChromeHover the text with Font Finder: a tooltip names the typeface your browser actually rendered — not just the first name in the CSS stack — with its weight and size. For lettering inside images, use a screenshot matcher instead; for live text, the page's computed styles are the ground truth.

Font Finder · How-to · TypographyHow to check font size and line height on a pageStart Font Finder's inspector and hover the text: the tip shows the rendered font size, and you can add line height to it in settings — or click to pin a card with size, line height and letter spacing, shown in px, pt or rem. Everything is computed locally in your browser.

Font Finder · Comparison · TypographyFont identifier Chrome extension: which kind to install (and what to check)A font identifier Chrome extension is one of two things: an image matcher that guesses fonts in pictures, or a live-page inspector that reads the exact rendered font of real text. For live text, pick an inspector that works without all-sites access — Font Finder shows the rendered family, weight and size on hover, free and fully local.

JSONPeek · How-to · JSONHow to view JSON in Chrome as a folded, searchable treeOpen the URL that returns JSON, click the JSONPeek icon and choose "Format this page". The raw text becomes a collapsible, searchable tree, rendered locally in the tab — the extension installs with access to no sites, and nothing is uploaded.

JSONPeek · How-to · JSONHow to format JSON in Chrome — one click, per site, or everywhereClick the JSONPeek icon and press "Format this page" for a one-off format, or flip "Always format JSON on <site>" to have that host's responses rendered the moment they load. The extension installs with zero site access, and formatting runs entirely in your browser.

JSONPeek · How-to · JSONHow to convert JSON to CSV locally, without uploading itOpen JSONPeek's Settings page, set the converter to From JSON → To CSV, and paste your data. The CSV appears live, converted entirely on your machine, and anything CSV can't express — nested objects, nulls, missing columns — is called out explicitly next to the result.

JSONPeek · How-to · JSONHow to pretty print JSON in the browserIf the JSON is a page, click the JSONPeek icon and press "Format this page". If it's a blob on your clipboard, paste it into the extension's converter with both formats set to JSON — it comes back indented, validated, and never sent anywhere.

JSONPeek · How-to · JSONHow to set up a Chrome JSON viewer extension — without giving it every siteMost JSON viewers demand "read and change all your data on all websites" the moment you install them. It doesn't have to work that way: install JSONPeek, which starts with access to no sites, format JSON pages with one click, and grant automatic formatting only to the hosts you actually choose.

NetworkRules · How-to · DeveloperHow to block unwanted redirects with a redirect blocker Chrome extensionAdd a rule with the Block action and a URL pattern matching the redirect target — or the script that triggers it — and matching requests are cancelled in the browser before they leave. The hit log and badge count show every request the rule stopped, so you can verify the blocker actually worked.

NetworkRules · How-to · DeveloperHow to redirect a URL or script to localhost with a Chrome redirect extensionAdd a rule with the Redirect action: match the production URL with a pattern, set the destination to your localhost address, and the browser loads your local file or API instead — on the live site, with no server or proxy changes.

NetworkRules · How-to · DeveloperHow to modify request headers in ChromeAdd a header rule with a URL pattern and the headers to set or remove — matching requests are rewritten locally as they leave the browser. Verify the change in the hit log, because DevTools can still display the headers as they looked before the rewrite.

Image OCR · How-to · OCRAn offline image to text converter for Chrome — no upload, everUse an extension that ships the OCR engine inside its own package. Recognition runs on your device, so converting an image to text works with Wi-Fi off and the picture never touches a server — no account, no per-page limit.

Image OCR · How-to · OCRHow to copy Chinese text from an image in ChromeSwitch the recognition language to 中文 + English and drop the image into a local OCR workspace. The Chinese language pack is bundled inside the extension, so recognition runs on your device — mixed Chinese/English text comes back in one editable pass, with no upload.

Image OCR · How-to · OCRHow to OCR a PDF page screenshot in ChromeWhen a PDF is scanned and its text won't select, screenshot the page and paste it into a local OCR workspace. The engine runs inside the extension, so the document is never uploaded — you get the passage back as editable text in seconds.

PDF Merge · How-to · PDFHow to reorder, rotate and delete PDF pages in ChromeOpen PDF Merge's Organize pages view: every page becomes a draggable tile you can reorder, rotate 90° or delete, then export the cleaned-up file. It all runs locally in your browser — the PDF is never uploaded.

PDF Merge · How-to · PDFHow to remove a password from a PDF locally (when you know it)If you know the password, open the PDF in PDF Merge in Chrome, unlock it — decryption happens on your device — and export an unencrypted copy. No honest tool can remove a password you don't know, and nothing here is uploaded.

PDF Merge · How-to · PDFHow to extract specific pages from a PDFOpen PDF Merge in Chrome, choose Split PDF → Extract pages, type a selection like 1-5, 8, 12-20 and export — the selected pages become one new PDF, produced entirely in your browser with nothing uploaded.

PDF to Image · How-to · PDFHow to convert a PDF to PNG in Chrome (lossless, no upload)Use PDF to Image, a free Chrome extension that renders each PDF page as a lossless PNG entirely on your device. Pick the pages, pick a clarity preset, convert — no upload site, no sign-up, and it works offline.

PDF to Image · How-to · PDFHow to extract pages from a PDF as imagesOpen PDF to Image, pick just the pages you need from the thumbnail grid — or type a range like 4, 9-12 — and export them as JPG or PNG. Everything renders on your device: no upload, no sign-up, works offline.

PDF to Image · How-to · PDFHow to convert a JPG to PDF in Chrome (no upload)Open PDF to Image, switch to Images → PDF, drop the JPG, pick a page size — or Fit to image — and save. The PDF is assembled on your device: no upload site, no sign-up, no print-dialog margins.

Image Converter · How-to · ImagesHow to save an image as PNG in ChromeChrome's built-in “Save image as…” can only save the file in its original format. Install Image Converter, right-click the image and choose Convert image to… → PNG: it re-encodes the image locally and downloads the PNG — no upload, no account. JPG and WebP work the same way, free.

Image Converter · How-to · ImagesHow to convert WebP to JPG in ChromeRight-click the WebP image and choose Convert image to… → JPG, or drop the file into Image Converter's popup. Set the quality (85 by default), pick a fill color for any transparent areas — JPEG has no transparency — and the JPG downloads. Everything runs locally; nothing is uploaded.

Image Converter · How-to · ImagesHow to convert images to AVIF in ChromeImage Converter encodes AVIF directly in your browser with a local WASM encoder — right-click an image and choose AVIF, or drop files into the popup. AVIF (like JXL) is a Pro format, unlocked with a one-time purchase; JPG, PNG and WebP conversion is free. Nothing is uploaded either way.

Image Converter · How-to · ImagesHow to batch convert images in ChromeOpen Image Converter's popup, pick the target format and quality, then drop all the files at once — up to 80 files or 400 MB per batch. Each image is converted locally and the results come back as a single ZIP. Batch is a Pro feature (one-time purchase); single images are free.

ProofJump · How-to · ResearchHow to ask questions about a web page in ChromeOpen ProofJump's side panel, type your question, and get an answer where every claim cites — and highlights — the exact sentence of the page it came from. Anything the page doesn't support is flagged "no source on page". You choose where the AI runs: on-device, your own API key, or Pro cloud.

ProofJump · How-to · ResearchHow to find where an article says something in ChromeWhen Ctrl+F fails because you remember the idea but not the wording, ask ProofJump's side panel "where does this article say …?" — it anchors the answer to the exact sentence and jumps you to it, highlighted in place. If the article never actually says it, you get "no source on page" instead of a stretch.

ProofJump · How-to · ResearchHow to summarize a web page with citations in ChromeAsk ProofJump's side panel to summarize the page: every line of the summary cites the exact sentence it came from, highlighted in place — click to verify. Lines the page doesn't support are flagged "no source on page", so the summary can't quietly drift from the source.

ProofJump · How-to · ResearchHow to research long documents faster in ChromeInstead of skimming a 40-page report, open ProofJump's side panel and interrogate it: ask targeted questions, jump straight to the sentences that answer them, and step through the evidence. Speed doesn't cost rigor, because every claim is anchored to the source — and gaps are flagged, not filled.

ReproKit · How-to · DeveloperHow to use a screen recorder Chrome extension for bug reportsPress record in the extension popup, reproduce the bug, then stop. Alongside the video, the extension captures the console output, the network requests as a HAR, your environment and your repro steps into one bundle — auto-redacted locally and reviewed by you before anything is shared.

ReproKit · How-to · DeveloperHow to use a screenshot Chrome extension that captures more than pixelsTake the screenshot from the extension popup, and capture it as part of a repro bundle: the image plus console output, network requests and environment details. Sensitive values are redacted locally, and you review the capture before sharing it.

ReproKit · How-to · DeveloperHow to use a screen capture Chrome extension that keeps everything localCapture a screenshot or screen recording from the extension popup — the capture is assembled in your browser, sensitive values are redacted on your machine, and nothing is uploaded unless you explicitly export or share it.

ReproKit · How-to · DeveloperHow to get a free screen recorder Chrome extension with no signupInstall ReproKit and press record — the free tier includes screen recording, screenshots, console and network HAR capture, repro steps and local redaction, with no account required for you or for anyone you ask to record a bug.

Screen Ruler · How-to · MeasurementScreen ruler Chrome extension: measure any web page in pixelsInstall Screen Ruler, click its icon on the tab you want to measure, and switch between drag measure, element measure, guides and a color loupe with keys 1–4. It installs with no site access — the overlay runs only where you invoke it, and Esc removes it.

Screen Ruler · How-to · ColorHow to pick a color from any web page in ChromeClick the Screen Ruler icon on the page, press 4 for the color loupe, and hover: a magnified view shows the exact pixel under the crosshair. Click to copy its value as HEX, RGB or HSL. Everything happens locally on the tab you invoked it on.

Screen Ruler · How-to · LayoutHow to add ruler guides to any web page in ChromeOpen Screen Ruler on the tab, press 3, and pull horizontal or vertical guides onto the live page — they stay put while you scroll, nudge by 1px with the arrow keys, and can be auto-spaced into an even grid. Esc removes everything.

Word Counter · How-to · Social mediaHow to check the character count for an X (Twitter) postSelect your draft — or paste it — and open Word Counter. The popup compares the character count to X's 280-character limit with an ok / near / over status, computed locally in your browser. Nothing is uploaded, and no account is needed.

Word Counter · How-to · SEOHow to check SEO title and meta description lengthSelect the draft title or description and open Word Counter — it compares the character count to the 60-character title and 160-character meta description guidelines, with an ok / near / over status. All counting runs locally; your unpublished copy is never uploaded.

Word Counter · How-to · WritingHow to calculate the reading time of any textSelect the text and open Word Counter — the popup shows an estimated reading time (240 words per minute by default) and speaking time (160 wpm), both adjustable in settings. The estimate is computed locally from your selection; nothing is uploaded.

Word Counter · How-to · WritingHow to count words in Chinese and Japanese correctlyCount Chinese and Japanese by character, not by spaces. CJK text has no word-delimiting spaces, so ordinary counters see a whole paragraph as one "word". Word Counter counts Han, Hiragana and Katakana per character, applies word rules to the Latin parts of mixed text, and runs entirely locally.

AuthRoam · How-to · DeveloperHow to switch between test accounts in Chrome without logging outLog in as each test account once, capture the token it sends in DevTools, and save it as a named environment — admin, member, trial. Then switch which account’s token is injected instead of logging out and back in. You still re-capture when a token expires; everything stays local.

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