utoolslib Logo

utoolslib

Data Stays on Your Device

Privacy-First
Developer Tools

Lightning-fast utilities that work 100% locally in your browser. No signup. No data collection. Just pure productivity.

28+ Tools
100% Free
No Signup
28 tools
Popular:JSONJSONBase64HTMLQRYAMLJSONText

100% Private

All processing happens locally in your browser. Your data never leaves your device.

Lightning Fast

Instant results with no server delays. Process large files at maximum speed.

Always Free

No hidden fees, no premium tiers. All tools are completely free forever.

Filter by:

Formatters

5
JSON Formatter
Format, validate, and beautify JSON data with syntax highlighting and error detection
JSON Beautifier
Beautify and fix broken JSON by adding missing quotes to keys and string values.
HTML Formatter
Format and beautify HTML code with proper indentation and syntax highlighting
CSS Minifier
Minify CSS code to reduce file size
SQL Formatter
Format and beautify complex SQL queries for better readability.

Encoders

3
Base64 Encoder/Decoder
Encode and decode Base64 strings instantly with download support
URL Encoder/Decoder
Encode and decode URLs for safe transmission
JWT Decoder
Decode and inspect JWT tokens. View header and payload.

Validators

2
JSON Validator
Validate JSON against schemas with error highlighting and schema generation
JSON Compare
Find differences between two JSON objects.

Generators

8
Password Generator
Generate secure passwords with customizable options
Hash Generator
Generate MD5, SHA1, SHA256 hashes from text
UUID Generator
Generate unique identifiers (UUID v1, v4)
Credit Card Generator
Generate dummy credit card numbers for testing and development.
JSON Generator
Generate random JSON objects for testing and development.
Paragraph Generator
Generate random placeholder paragraphs for testing and design.
QR Code Generator
Generate QR codes for URLs, text, or any data. Download and share instantly.
Chmod Calculator
Calculate Linux file permissions (e.g., 777, 755) using checkboxes or numeric input.

Testing

2
Regex Tester
Test and debug regular expressions with real-time matching
Text Diff Checker
Compare two texts or code snippets to find differences (lines added, removed, or modified).

Design

2
Color Picker
Pick colors and convert between HEX, RGB, HSL formats
Gradient Maker
Create beautiful CSS gradients and copy the code.

Converters

6
Timestamp Converter
Convert between Unix timestamps and human-readable dates
Image Compressor
Compress images to reduce file size without losing quality.
Image Converter
Convert images between formats (JPG, PNG, WebP, etc).
YAML ↔ JSON Converter
Convert between YAML and JSON formats instantly. Paste your data and switch formats for easy integration.
JSON ↔ TOON Converter
Convert between JSON and TOON (Token-Oriented Object Notation) to reduce token count for transmission and LLM usage.
String Case Converter
Convert text between camelCase, snake_case, kebab-case, PascalCase, and detailed title case.