Free developer tools that run in your browser

No signup, no uploads, no tracking of your data. Every tool computes locally — your data never leaves your device.

JSON Formatter & Validator

Pretty-print, minify and validate JSON with precise error locations.

JSON to CSV Converter

Convert JSON arrays to CSV, ready for Excel or Google Sheets.

JSON to TypeScript

Generate TypeScript interfaces from any JSON sample.

JSON to XML Converter

Convert JSON objects and arrays to clean, readable XML.

JSON to YAML Converter

Convert JSON to YAML for configs, Kubernetes and CI pipelines.

XML to JSON Converter

Convert XML documents to JSON, with attributes and arrays preserved.

JSON Escape / Unescape

Escape text into a JSON string literal and back, plus URL encoding.

JSON Flatten / Unflatten

Flatten nested JSON to dot notation and reconstruct it.

JSON Key Sorter

Sort JSON object keys alphabetically, recursively.

SQL Formatter

Beautify SQL for MySQL, PostgreSQL, SQLite, T-SQL, PL/SQL and more.

CSS Formatter & Minifier

Beautify stylesheets for reading, minify them for shipping.

XML Formatter & Minifier

Re-indent messy XML or strip it down for transport.

URL & Query String Parser

Break a URL into protocol, host, path and parameters.

HTTP Header Formatter

Convert raw HTTP headers to JSON and back.

Cookie Parser & Formatter

Parse cookie strings into structured JSON with attributes.

Base64 Encode / Decode

UTF-8 safe Base64 with URL-safe variant support.

Hash Generator

MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC32 at once.

JWT Decoder

Decode JWT header and payload, check expiry locally.

UUID Generator

Bulk-generate cryptographically random UUID v4.

Password Generator

Strong random passwords with charset control.

AES-256 Encrypt / Decrypt

Password-based AES-GCM encryption, fully in-browser.

Encode / Decode

Escape or unescape HTML special characters.

Unicode Converter

Convert text to \uXXXX escapes and back.

Cron Expression Generator

Build, validate and decode cron expressions with next-run preview.

Image Compressor

Compress and resize PNG, JPG and WebP images — 100% in your browser.

More tools coming soon

PDF tools, HEIC conversion, encoding utilities and more.

Why local-first tools?

Most online tools upload your data to a server before returning a result. BasaltKit tools run entirely in your browser: faster responses, works offline, and sensitive data — API keys, customer records, private images — never leaves your device.