JSON Formatter
Beautify & validate JSON with configurable indentation
JSON Minifier
Compress JSON by removing all whitespace
JSON to CSV
Convert JSON arrays to CSV with nested object support
JSON to YAML
Convert JSON to YAML format
CSV to JSON
Convert CSV to JSON with type inference
CSV Viewer
View, sort, and filter CSV data in a table
Base64 Encode
Encode text or files to Base64
Base64 Decode
Decode Base64 strings to text
SQL Formatter
Beautify SQL queries with dialect support
YAML to JSON
Convert YAML to JSON format
Text Diff
Compare two texts and highlight differences
URL Encode
Percent-encode text for safe use in URLs
URL Decode
Decode percent-encoded URL strings
HTML Encode
Escape special characters to HTML entities
HTML Decode
Decode HTML entities back to text
Markdown to HTML
Convert Markdown to HTML
Regex Tester
Test regular expressions with live matching
Hash Generator
Generate SHA-1, SHA-256, and SHA-512 hashes
UUID Generator
Generate random v4 UUIDs
Timestamp Converter
Convert Unix timestamps to dates and back
Color Converter
Convert colors between Hex, RGB, and HSL
JWT Decoder
Decode and inspect JWT tokens
Cron Parser
Explain cron expressions in plain English
HTML to Markdown
Convert HTML to Markdown
Developer tools that respect your data and your time
DevFmt is a free collection of fast, privacy-first formatting and conversion tools for developers, data engineers, and anyone who works with structured data. Format and validate JSON, convert between JSON, CSV, and YAML, encode and decode Base64 and URLs, format SQL, decode JWTs, test regular expressions, generate hashes and UUIDs, and more — all from one clean, keyboard-friendly workspace.
Everything runs in your browser
Unlike many online formatters, DevFmt never uploads your data. Every tool processes your input locally using JavaScript — there is no backend that receives, stores, or logs what you paste. That means you can safely format production API responses, configuration files, access tokens, and other sensitive data without it ever leaving your machine. You can verify this yourself in your browser’s network tab.
Built for speed
No sign-up, no paywalls, and no intrusive pop-ups. Tools load instantly and process input as you type. Paste detection routes your clipboard to the right tool automatically, and keyboard shortcuts keep your hands off the mouse.
One toolkit, many formats
DevFmt covers the conversions and transformations developers reach for every day: JSON formatting and minification, JSON, CSV, and YAML conversion, Base64 and URL encoding, HTML entity escaping, Markdown and HTML conversion, SQL beautification, regex testing, hashing, UUID generation, timestamp conversion, color conversion, JWT decoding, and cron expression parsing. New tools are added regularly.
Browse the full list above, or read our developer guides to learn more about each format and when to use each tool.