Free Developer Tools — JSON, Base64, JWT & More
Lightning-fast utilities for JSON, Base64, JWT, regex, hashes and more. Every tool runs in your browser — your data never leaves your device.
JSON & Data
JSON Formatter
Format, validate, minify and inspect JSON instantly in your browser.
Open toolYAML ↔ JSON
Convert between YAML and JSON with a single click.
Open toolCSV to JSON
Convert CSV/TSV data into JSON with header detection.
Open toolJSON to Types
Generate TypeScript, Go, Python, Rust and Java types from JSON.
Open toolEncoding & Hashing
Base64 Encode/Decode
Encode or decode Base64 text and files with auto-detection.
Open toolURL Encoder/Decoder
Encode, decode and parse URLs with a built-in query parameter editor.
Open toolHash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 hashes from text or files.
Open toolHTML Entity Encode/Decode
Encode and decode HTML entities — named, numeric, and hex.
Open toolAuth, Certs & Keys
Text & Code
Regex Tester
Test and debug regular expressions with real-time match highlighting.
Open toolDiff Checker
Compare two text blocks and see line and word differences.
Open toolCSS/JS Minifier
Minify CSS and JavaScript locally with size savings reported.
Open toolSQL Formatter
Format SQL for any major dialect with proper indentation.
Open toolMarkdown Preview
Preview Markdown side-by-side with rendered HTML and GFM support.
Open toolGenerators & Time
UUID Generator
Generate UUID v4 / v7 / GUIDs in bulk with one click.
Open toolUnix Timestamp Converter
Convert between Unix epoch timestamps and human-readable dates.
Open toolCron Expression Generator
Build and decode cron expressions with next-run previews.
Open toolLorem Ipsum Generator
Generate Lorem Ipsum placeholder text by words, sentences or paragraphs.
Open toolTimezone Converter
Compare a time across many timezones at once — IANA-aware, DST-correct.
Open toolPassword Generator
Generate secure passwords or EFF-wordlist passphrases. Crypto-secure, client-side.
Open toolNetwork
HAR File Analyzer
Analyze HAR files with a waterfall, slowest requests and domain breakdown.
Open toolDNS Lookup
Look up A, AAAA, MX, TXT, NS, CAA and more — via DNS-over-HTTPS.
Open toolWhat's My IP
Public IP, country, and everything your browser exposes — one glance.
Open toolReverse DNS Lookup
Look up PTR records for IPv4 / IPv6 with FCrDNS verification. Bulk mode supported.
Open toolDesign & AI
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Private by design
Every tool here runs entirely in your browser. Your data is never uploaded, stored or transmitted to our servers. That means faster results — and total privacy.
Built for developers
Whether you're debugging an API response, decoding a JWT, hashing a file or testing a regex, XpressDevTools gives you the right tool without sign-ups, ads in the workflow, or hidden limits.
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