Every tool, one place
Developer tools that run in your browser
One site, the whole toolbox. Diff two files, decode a token, format some JSON, hash a string — without opening four different tabs and without handing your data to any of them.
Everything here runs on your own machine. Nothing you paste is sent anywhere — no fetch, no logging, no third-party scripts on any tool page. No sign-up, no request limits.
Live now
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The whole toolbox
Twenty-five of thirty-seven are built. The rest are on the bench, in roughly this order. Nothing below is a link yet — when it is built, it appears above and turns into one.
Text and data
- Compare text
- JSON formatter
- Markdown editor
- Fake data generator, UK-flavoured
- Secret and API key redactor
- Text case converter
- EXIF data viewer and stripper
- Whitespace / line-ending converter
Encoding and crypto
- Hash and HMAC generator
- JWT decoder and verifier
- Base64 for text, files and images
- URL encode and decode
- Query-string parser and builder
- Password strength checker
- Passphrase generator
- QR code generator and reader
- Key format converter (PEM/JWK/DER)
Developer utilities
- Cron expression builder with next-run preview
- UUID, ULID and NanoID generator
- Regex tester, with a PCRE/Python/POSIX flavour reference
- Epoch and timezone converter
- curl converter, to fetch, axios, Python or C#, and back
- CIDR and subnet calculator
- chmod calculator
- .gitignore generator
- Dockerfile generator
- CSS gradient generator
- CSS box-shadow generator
- CSS border-radius generator
- Favicon generator
- HTTP status code reference
- Number base converter
- .editorconfig generator
- Docker Compose generator
- Meta tag / Open Graph generator
- robots.txt generator and validator
- Semver calculator
- License picker (SPDX)
Why it works this way
Your data stays put
Developers paste live secrets into token decoders and .env parsers on strangers' websites every day. Here the processing happens in your own browser, so there is nothing to send and nothing to leak.
No adverts, no trackers
No ad network, no analytics tag, no session recording, no hosted libraries. That is what makes the line above true rather than a claim.
No account on the free tools
Nothing above asks who you are or stops working after fifty uses. There is nothing to meter — the code runs on your machine, not on a server of ours, so a usage counter would be counting nothing.
It loads and it works
Static pages, no framework, no build step. Keyboard focus is visible everywhere, it works down to a phone, and it respects reduced motion.
What will cost money, and why
Some tools cannot run in your browser. Anything that has to receive a request from somewhere else needs a server sitting on the internet waiting for it — and a couple of tools need a server for a different reason: they have to reach out in ways a browser is deliberately blocked from doing, such as reading an arbitrary site's response headers across origins, or opening a raw socket to inspect a certificate. Those are the ones that will be paid, and they are the only ones.
Planned paid tools
- Request bin — capture and inspect any HTTP request
- Custom responses — status codes, bodies, headers, delays
- Mock API endpoints with rule-based responses
- Mock SMTP inbox with a unique address
- HTTP header inspector — read any URL's response headers server-side, sidestepping the CORS restriction that blocks this in the browser
- Certificate and SSL checker — opens a raw TLS connection to inspect a certificate, which needs a server socket no browser API provides
- Forward captured requests to localhost
- Sample Stripe, GitHub and Shopify payloads on demand
- Webhook signature verifier
They will need an account. A server has to know whose captured requests are whose. There is no way round that, and pretending otherwise would be dishonest.
They will be kept separate. Different part of the site, clearly marked, so you always know whether what you are using touches a server or not.
The free tools stay free. Unlimited, no sign-up, no counter — not as a promotion, but because they cost nothing to run. There is no version of this where they get metered later.
Nothing is priced yet and nothing is for sale. When it is, the price will be on the page before you are asked for an email address.