Free Online Tools for Developers & Creators
Fast, private, and easy-to-use tools that run entirely in your browser. No sign-up, no data collection, no limits.
Developer Tools
JSON Formatter
Format, validate, and minify JSON data with syntax highlighting and error detection.
Regex Tester
Test regular expressions in real-time with match highlighting and group extraction.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text input.
Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 strings back to plain text instantly.
URL Encoder/Decoder
Encode and decode URLs with percent-encoding for safe transmission.
CSS Minifier
Minify CSS code to reduce file size and improve page loading speed.
Diff Checker
Compare two texts side-by-side with highlighted additions, deletions, and changes.
JWT Decoder
Decode JSON Web Tokens to inspect header, payload, and expiration status.
Cron Expression Generator
Build cron expressions visually with human-readable descriptions and next-run preview.
JSON / YAML Converter
Convert between JSON and YAML formats with syntax validation and formatting options.
HTML Entity Encoder
Encode and decode HTML entities with a searchable reference table of 100+ entities.
Design Tools
Image Compressor
Compress JPEG, PNG, and WebP images in your browser with before/after comparison.
CSS Gradient Generator
Create beautiful linear, radial, and conic gradients visually with 20+ presets.
Box Shadow Generator
Design multi-layer CSS box shadows with live preview and preset styles.
Generators & Converters
Password Generator
Generate cryptographically secure passwords with strength analysis and batch mode.
UUID Generator
Generate universally unique identifiers (UUID v4) with bulk generation support.
QR Code Generator
Generate QR codes from text or URLs with custom colors and sizes. Download as PNG.
Color Picker & Converter
Pick colors, convert formats, check WCAG contrast, and generate gradients.
Number Base Converter
Convert between binary, octal, decimal, and hex with interactive bit visualization.
Timestamp Converter
Convert between Unix timestamps and human-readable date/time formats.
Lorem Ipsum Generator
Generate placeholder text in paragraphs, sentences, or words for your designs.
Markdown Preview
Write and preview Markdown with live rendering and export to HTML.
Text Counter
Count words, characters, sentences, and paragraphs with reading time estimation.
AI & Prompt Tools
Text to Speech AI
Generate natural AI speech in your browser. 10 voices, adjustable speed, WAV download. 100% local & private.
Token Counter AI
Estimate token counts for GPT-4o, Claude, Gemini, and Llama. Calculate API costs instantly.
Prompt Builder AI
Build reusable prompt templates with variables. 8 built-in templates, save to localStorage.
Productivity Tools
Case Converter
Convert text between camelCase, snake_case, kebab-case, and 9 more formats instantly.
CSV / JSON Converter
Convert between CSV and JSON formats with table preview and file drag-and-drop.
Unit Converter
Convert between length, weight, temperature, area, volume, data, time, and speed units.
Pomodoro Timer
Stay focused with customizable work/break intervals, sound alerts, and daily statistics.
Why TensorLocal?
Lightning Fast
All tools run entirely in your browser. No server round-trips, instant results.
100% Private
Your data never leaves your device. We don't collect, store, or transmit anything.
Completely Free
All tools are free to use with no limits, no sign-up, and no hidden fees.
Works Everywhere
Fully responsive design that works on desktop, tablet, and mobile devices.