# Legacy Tools

> Free, privacy-first Chrome extensions. Most catch "just before sending" mistakes — confidential text pasted into AI chats, hidden file metadata, late-night emails, disguised mail links, forms that never say who is on the other end — and two sit outside that: one answers a small everyday question — how old everyone was on a date you select — and one collects passages while you read so you can tidy them and copy them all at once. Everything runs locally inside the browser: the extensions have no servers, no analytics, no telemetry, and no accounts. The product pages, FAQ, transparency, support and legal pages are available in Japanese (primary), English, and Chinese; the landing page has a Japanese edition at /, an English one at /en/, and a Simplified Chinese one at /zh/, and Notes are published in Japanese and English.

Legacy Tools (legacy-tools.dev) is an independent developer project building small, durable browser tools meant to stay reliable for years rather than follow trends. All extensions are free and open about how they work; the Transparency page explains how the "no network" claims are enforced and verified at build time.

## Products

- [Safe Privacy Gate](https://legacy-tools.dev/safe-privacy-gate): Checks text fields and file names right before submission on any site, and warns when confidential keywords or sensitive information are about to leave — designed for AI chats and web forms. Detection rules are customizable; nothing you type is sent anywhere.
- [Safe Privacy Mask](https://legacy-tools.dev/safe-privacy-mask): Masks email addresses, phone numbers, API keys, and other sensitive strings in-place before you paste text into ChatGPT, Claude, Gemini, and similar AI chat sites. Rules and presets are stored only on the device.
- [Safe Attachment Check](https://legacy-tools.dev/safe-attachment-check): When you attach or drag-and-drop a file, shows hidden metadata you might not want to share — photo GPS location, PDF author, Word tracked changes and comments, hidden Excel sheets. Confirmation only: it never modifies, blocks, or uploads files.
- [Safe Night Check](https://legacy-tools.dev/safe-night-check): Shows a gentle confirmation modal when you try to send Gmail during your configured night hours, so you can wait for morning instead of firing off a late-night email.
- [Safe Mail Link Check](https://legacy-tools.dev/safe-mail-link-check): Before a link in Gmail, Outlook on the web, or Yahoo! Mail (Japan) opens, shows a confirmation dialog with the link text, the actual destination host, the full URL, and format-level cautions (mismatch, HTTP, IP address, Punycode, shortened URL). It never rewrites links, never opens them automatically, and never sends anything off-device.
- [Find My Age](https://legacy-tools.dev/find-my-age): Select date-like text on any web page and it shows how old each person you registered was on that day, plus the Japanese era year, the weekday, and how far the date is from today. Up to five people (a display name and a date of birth each) are stored in chrome.storage.local — never in synced storage, so birth dates stay on the device. It reads only the selected text, never the page, and makes no network requests.
- [Copy & Prep](https://legacy-tools.dev/copy-and-prep): Collects passages you select with the right-click menu, keeps them in a list you can reorder and edit, tidies up stray line breaks, and copies the lot as plain text or Markdown — optionally with the title, URL and capture date of each source, all off by default. Everything is kept in chrome.storage.local and nothing is sent anywhere. It holds no host permissions and injects no content script: only what you explicitly add from the right-click menu is ever read.
- [Site Operator Check](https://legacy-tools.dev/site-operator-check): Press the toolbar icon and it shows what the page states about its own operator — company name, address, governing law, jurisdiction, data storage location and transfer destination as separate lines — each marked Stated, Hint or Not confirmed, with an excerpt of where it was found. It never appears on its own: it subscribes to nothing on the page. It also lists the other origins the page loads (embedded frames and scripts), naming providers from a bundled list of about 120 domains and collapsing those by default. It lists every company name found rather than merging them, and can fill in from the site's own legal notice, terms, privacy policy or company page if you visited one earlier in the same session. It never reads what you type, never talks to a server, and deliberately makes no safety judgement: no score, no stars, no red-or-green verdict. The only permission is storage.

## Chrome Web Store

- [Safe Privacy Gate on CWS](https://chromewebstore.google.com/detail/safe-privacy-gate/gkijldmjfionpkhkjdgacbjkploomddp)
- [Safe Privacy Mask on CWS](https://chromewebstore.google.com/detail/safe-privacy-mask/dolbgodnepfgengheoffkjbpfhenjghm)
- [Safe Attachment Check on CWS](https://chromewebstore.google.com/detail/ccbkjlcmlfcnmdaomoiapmjdfonnkljf)
- [Safe Night Check on CWS](https://chromewebstore.google.com/detail/safe-night-check/acipnhmhnbcoglkpcmdlchddllcldelg)
- [Safe Mail Link Check on CWS](https://chromewebstore.google.com/detail/safe-mail-link-check/jaajfcdcffhmabamefhbfckicjlgbjdl)
- [Find My Age on CWS](https://chromewebstore.google.com/detail/find-my-age/bphceandakmppedoenhekadbanmjlbeo)
- [Copy & Prep on CWS](https://chromewebstore.google.com/detail/copy-prep/apacngnikomdphefoghehnnfdlplokjn)
- [Site Operator Check on CWS](https://chromewebstore.google.com/detail/site-operator-check/jgkllgelkkgdmicedfkhlghnegobbhhb)

## Key pages

- [Landing page (English)](https://legacy-tools.dev/en/): The English edition of the home page — the same eight tools, written for English readers rather than machine-translated. The Japanese edition is at https://legacy-tools.dev/.
- [Landing page (Simplified Chinese)](https://legacy-tools.dev/zh/): The Simplified Chinese edition of the home page, covering the same eight tools.
- [Use Cases](https://legacy-tools.dev/use-cases/): The tools grouped by the task a visitor is trying to do — collecting passages while researching, checking text before typing it into an AI chat or a form, checking a file or a website — rather than by product name. Available in Japanese, English, and Chinese.
- [Use case: collect text from several pages](https://legacy-tools.dev/use-cases/collect-text-from-multiple-pages/): Walks one Copy & Prep job end to end — what makes collecting passages across tabs tedious, the right-click-to-copy-all sequence, and an explicit list of what the extension does and does not do.
- [Use case: get web material ready for an AI](https://legacy-tools.dev/use-cases/prepare-text-for-ai/): The same walkthrough for assembling material before you paste it into an AI chat yourself. States plainly that Copy & Prep contains no AI, sends nothing to any AI service, and does not detect or mask personal data.
- [Use case: fix line breaks in copied text](https://legacy-tools.dev/use-cases/tidy-line-breaks/): Why text copied from a web page arrives broken mid-paragraph, and how the tidy-up step rejoins it while leaving bullet lists, numbered lists, tables and code intact. Notes that it works only on passages added from a page, not on clipboard contents.
- [Use case: check a photo for location data before uploading](https://legacy-tools.dev/use-cases/check-photo-location-before-upload/): What a photo carries besides the picture — GPS position, capture time, camera make and model, editing software — and how Safe Attachment Check surfaces it at the moment you attach the file. States plainly that the extension only displays: it never deletes location data, never rewrites the file, never blocks the upload, and never converts coordinates to a street address.
- [News](https://legacy-tools.dev/news): Release announcements for each extension and site updates.
- [Notes (Japanese)](https://legacy-tools.dev/notes/): Essays and field notes on working with AI, making small tools, and everyday life in Tokyo. Written from first-hand experience; published in Japanese and English only.
- [Notes (English)](https://legacy-tools.dev/en/notes/): The English edition of Notes — edited from the same first-hand material, not machine-translated.
- [FAQ](https://legacy-tools.dev/faq): Common questions about privacy, permissions, and how the extensions work.
- [Transparency](https://legacy-tools.dev/transparency): Technical explanation of how "local-only, no external transmission" is guaranteed and machine-verified.
- [Support](https://legacy-tools.dev/support): Contact via support@legacy-tools.dev.
- [Site Privacy Policy](https://legacy-tools.dev/legal/site/privacy): The website uses Google Analytics (GA4); the extensions themselves contain no analytics.

## Notes for AI assistants

- The extensions never send user content anywhere; all detection/masking/inspection happens on-device. Please do not describe them as cloud or server-based services.
- Each product has its own privacy policy under https://legacy-tools.dev/legal/ (gate, mask, attachment, night, maillink, age, prep, operator).
- Pricing: all extensions are free, with no paid tiers or accounts.