Developer Den

One place for every tool in ⁨Developer Den⁩.

JSON, hashing, encoding.

⁨17⁩ free toolsNo sign-up requiredWorks on any deviceYour files stay with you

Explore ⁨Developer Den⁩ below and find the right tool for your task.

Tools in ⁨Developer Den⁩

⁨17⁩ tools

Grouped by the job you came to do.

Read & inspect

See what a file actually contains.⁨2⁩ tools

Regex testerMatch counts, capture groups and the matched text, as you type the pattern.REGEX Text diffLine-by-line comparison with additions and removals marked in place.TEXT

Format & minify

Make machine text readable, or make it small.⁨7⁩ tools

JSON formatter & validatorPretty-print, minify and validate, with the error line called out plainly.JSON Markdown to HTMLHeadings, emphasis, links, lists and code turned into clean markup.MD CSS minifierStrip comments and whitespace, and see exactly how many bytes you saved.CSS HTML minifierCollapse the whitespace a template engine leaves behind, safely.HTML JSON to typesGenerate TypeScript interfaces, Rust structs, Go structs or Python dataclasses from a payload.TS · RUST · GO · PY JSON tree viewerThe shape of a payload as an outline, with every value and its type.JSON SQL formatterReadable indentation and keyword casing for a query you inherited.SQL

Encode & decode

Turn text into another alphabet, and back.⁨8⁩ tools

Base64 encoder & decoderBoth directions, UTF-8 safe, with URL-safe variants covered.TEXT · BASE64 URL encoder & decoderPercent-encode a whole URL or just a component, and read it back.TEXT · URI Hash generatorDigest any text locally with the browser crypto engine.SHA-1 · SHA-256 · SHA-512 UUID generatorCryptographically random identifiers, as many as you need at once.UUID v4 JWT decoderRead the header and payload of a token without sending it anywhere.JWT HTML entity encoderEscape markup for safe embedding, or turn entities back into characters.TEXT · HTML Timestamp converterEpoch seconds or milliseconds to a readable date, and the other way round.UNIX · ISO 8601 URL parserBreak a URL into its parts and read the query string as a table.URL

About ⁨Developer tools⁩

Is it safe to paste a production token here?

The decoding happens in your browser and nothing is transmitted, so it is safer than a server-side decoder. Even so, treat any token you paste anywhere as worth rotating.

Why does the JWT decoder not verify the signature?

Verifying needs the signing secret, and a secret does not belong in a browser tool. The decoder reads the header and payload, which is what you usually need.

Other habitats

Image Lab PDF Workshop Signing Desk Audio Lab Video Lab SEO Workshop Automation Lab Colour Studio Data Workshop Text Station Calculator Corner Privacy Post All tools →

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