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🛠️ 20 Developer Tools

Free Online Developer Tools

Format JSON, encode Base64, generate cryptographic hashes, test regex, create secure passwords and UUIDs — every tool a developer needs, available instantly in your browser.

✅ No Login⚡ Real-time Results🔒 Web Crypto API🚫 No Server

All Developer Tools

From data formatting to security utilities — all free, all instant

JSON Formatter & Validator
Format, beautify, validate and minify JSON in real-time. Sort keys alphabetically, choose indent size, paste to auto-format. Shows exact error location on invalid JSON.
Format / MinifyValidateSort keysReal-time
Base64 Encode / Decode
Encode text or files to Base64, decode Base64 strings back to text. Supports URL-safe Base64 variant. Upload any file to get its Base64 data URI — handy for embedding images in CSS.
Text & FilesURL-safeData URIImage preview
URL Encoder / Decoder
Percent-encode strings for safe use in URLs. Decode percent-encoded strings back to readable text. Supports both encodeURIComponent and encodeURI modes. Real-time as you type.
Percent-encodingencodeURIComponentReal-time
Hash Generator (SHA-256, SHA-512)
Generate SHA-1, SHA-256, SHA-384, SHA-512 hashes for text or files using the Web Crypto API. Hash files up to 100MB. Compare two hashes to verify file integrity.
SHA-256SHA-512File hashingHash compare
UUID v4 Generator
Generate RFC 4122 compliant UUID v4 values using cryptographically secure randomness. Bulk generate up to 100. Format as standard, uppercase, no-hyphens, URN or braces. Includes UUID validator.
UUID v4Bulk (100)Multiple formatsValidator
Regex Tester & Debugger
Test regular expressions with real-time match highlighting. See all matches, capture groups, and match positions. Supports g, i, m, s flags. Includes common patterns library (email, URL, phone).
Real-timeCapture groupsAll flagsCommon patterns
CSS Minifier & Beautifier
Minify CSS to reduce file size, or beautify minified CSS back into readable code. Shows size reduction percentage.
MinifyBeautifySize stats
JavaScript Minifier & Beautifier
Safely minify JS by removing comments and whitespace without renaming variables, or beautify minified code.
String-safeBeautify
HTML Minifier & Beautifier
Minify HTML by removing comments and whitespace, or beautify with proper indentation.
MinifyBeautify
HTML Entity Converter
Encode special characters as HTML entities, or decode entities back to text.
EncodeDecode
Cron Expression Builder
Build cron expressions visually with plain-English explanation.
Visual builder
JWT Decoder
Decode JWT header and payload claims instantly.
Client-side only
SQL Formatter
Beautify messy SQL queries into readable, indented code.
Auto-indent
CSS Gradient Generator
Build linear and radial gradients visually with CSS output.
Visual builder
CSS Box Shadow Generator
Build box shadows visually with instant CSS code.
Visual builder
HTTP Status Code Lookup
Searchable reference of all common HTTP status codes.
Searchable
XML Formatter & Validator
Format, validate, and minify XML documents.
Validates syntax
YAML to JSON Converter
Convert between YAML and JSON, both directions.
Nested support
CSS Clamp() Calculator
Generate fluid, responsive font-size clamp() values.
Live preview

About Logrith Developer Tools

Developer tools are utilities that programmers, DevOps engineers, and technical users need constantly — but shouldn't have to install software or sign up for services to access. Logrith's developer tool collection covers the most frequently needed utilities, all running in the browser with zero setup.

The JSON Formatter is one of the most-used tools — it validates JSON with precise error location, beautifies minified JSON for readability, and minifies formatted JSON for production. The key sorting feature is particularly useful for standardizing API response formats and configuration files.

For security-sensitive tasks, Logrith uses the browser's built-in Web Crypto API — the same cryptographic primitives used by the operating system itself. The Hash Generator uses SubtleCrypto.digest() for SHA-256/SHA-512, and the Password Generator uses crypto.getRandomValues() for cryptographically secure randomness. Neither tool has any external dependencies for their core functionality.

The Regex Tester uses the browser's native RegExp engine — the same one your Node.js or frontend JavaScript will use — so test results here match exactly what you'd get in production JavaScript code. This is a key advantage over server-based regex testers that may use different regex flavors (PCRE, Python re, etc.).

Frequently Asked Questions

Which hash algorithm should I use for password storage?
None of the hashes in this tool (SHA-256, SHA-512) are appropriate for password storage — they're too fast, which makes brute-force attacks easy. For password hashing, use bcrypt, Argon2id, or scrypt with a high cost factor. These tools are for checksums, data integrity verification, and non-security uses.
Is the JSON formatter safe for sensitive API data?
Yes. All JSON processing happens in browser memory only — no data is sent to any server. You can even disconnect from the internet after loading the page and the formatter will continue to work perfectly.
What's the difference between encodeURIComponent and encodeURI?
encodeURI encodes a complete URL, preserving characters like /, ?, &, =, # that have structural meaning. encodeURIComponent encodes everything except unreserved characters — use it for values inside query parameters. For query string values, always use encodeURIComponent.
Can I use these tools in a CI/CD pipeline?
These tools are web-based and interactive — they're designed for manual use. For CI/CD pipelines, use command-line tools like jq (JSON), openssl (hashing), or uuidgen. Logrith is designed for developer convenience in the browser, not scripted automation.
How do I test a regex that should match email addresses?
Open the Regex Tester and click the "📧 Email" button in the common patterns section to load a standard email regex. Then modify your test string. You can adjust the regex directly — all matches are highlighted in real-time as you type.
What Base64 variant should I use for JWT tokens?
JWT tokens use URL-safe Base64 (Base64url) — which replaces + with - and / with _, and omits padding = characters. Select "URL-safe Base64" in the encoding mode dropdown of the Base64 tool. The standard variant (+/=) should not be used directly in URLs or HTTP headers.
What is UUID v4 and when should I use it?
UUID v4 is a randomly generated 128-bit identifier in the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx. Use it as database primary keys, session tokens, file upload names, or any identifier that needs to be unique without central coordination. The collision probability is negligible — about 1 in 5.3 × 10^36.
How accurate are the password crack time estimates?
The estimates assume pure brute-force attacks through the entire keyspace. Real attacks often use dictionary attacks and rule-based generation that can crack common patterns much faster. The estimates give a theoretical upper bound — in practice, any password based on dictionary words or common patterns is much weaker than the entropy-based calculation suggests.
Can I format very large JSON files?
The JSON formatter works on any size that fits in browser memory — typically up to 50–100MB of JSON text without issues on modern devices. Very large JSON files (hundreds of MB) may cause browser tab memory limits to be hit. For extremely large files, use jq in the command line instead.
Are there plans to add an HTML formatter or XML formatter?
Yes, both HTML and XML formatters are on the roadmap. HTML formatting will use the browser's DOMParser to parse and reserialize with proper indentation. XML formatting will similarly leverage the DOMParser's native XML processing capabilities for browser-native results.