Developer Tools

Formatters, encoders, generators and testers for developers. Nothing is sent to a server.

JSON Formatter & ValidatorPaste JSON, get it beautified, minified or validated with the exact line and column of the problem. Everything runs in your browser.
Cron Expression GeneratorWrite a cron expression in Unix, Spring or Quartz form, read what it actually means in English, and see the next ten fire times in UTC and your local time.
Base64 Encoder & DecoderConvert text, files and data URIs to and from Base64 with correct UTF-8 handling, a URL-safe option and MIME line wrapping. Nothing is uploaded.
Unix Timestamp ConverterA live epoch clock, instant timestamp-to-date conversion in UTC and your local time, a date-to-timestamp direction, and a batch mode for whole log columns.
Password GeneratorBuild a random password or a memorable passphrase with real cryptographic randomness. Entropy, strength and crack time are shown for the exact options you picked — and nothing ever leaves your browser.
UUID GeneratorCreate random or time-ordered identifiers in bulk, format them for JSON, CSV or a SQL insert, and paste any existing id to find out which version it is and when it was made.
Hash GeneratorCompute SHA and CRC32 digests of text or files entirely in your browser, switch between hex and Base64, sign messages with HMAC, and check two hashes against each other.
URL Encoder & DecoderEncode or decode percent-escapes with precise error messages, rebuild a query string from an editable table, and see exactly which part of a URL is which.
JWT DecoderPaste a JWT to read its header and payload, understand every claim in plain English and see at a glance whether it is still valid. The signature is not verified, and the token never leaves your browser.
CSV ⇄ JSON ConverterPaste or drop a file and convert between CSV and JSON in both directions, with a proper RFC 4180 parser that handles quotes, commas inside values and multi-line fields.
Color ConverterPaste a colour in any notation and get every other one back, plus tints, shades and harmony palettes and a contrast check that tells you straight out whether text will be readable.

Everyday utilities for developers

These tools cover the small tasks that interrupt real work: checking a payload, decoding a token or generating an ID. Every one of them runs locally, which matters when the data is a production token or a customer record.

Data formats. The JSON formatter validates and pretty-prints JSON with exact error positions, and the CSV to JSON converter handles quoted fields, custom delimiters and nested keys in both directions.

Encoding and security. Use the Base64 encoder and the URL encoder for safe transport of text and binary data. The JWT decoder reads a token’s header and claims and tells you when it expires. The hash generator computes SHA-family hashes and HMACs, and the password generator creates strong passwords and passphrases with the entropy shown.

Identifiers and time. The UUID generator supports v4, time-ordered v7 and ULID. The Unix timestamp converter translates epoch times, and the cron expression generator explains and previews Unix, Spring and Quartz schedules.

Design. The color converter translates between HEX, RGB, HSL and CMYK and checks WCAG contrast.

Nothing leaves your browser

There are no API calls behind these tools. Tokens, keys and payloads are processed in memory in the page and discarded when you close it.