Free Online Tools & Brain Games

Every tool runs locally in your browser — your data never leaves the device. Games need no sign-up, just click and play.

87Online tools

10Brain games

12Categories

2Languages

All Categories

12

Convert between text encodings and data formats

Hash & Crypto 13

Hashing, key generation and encryption checks

Data & Format 12

Convert and beautify JSON, XML, YAML, CSV

Regex, cron, JWT, SQL and everyday dev helpers

IP, subnet, MAC and port calculations

Case, stats, dedupe and cleanup for text

Image & Media 6

QR codes, placeholders and image helpers

Percentages, temperature, dates and units

Hand-eye coordination and reaction speed

Sequence and working memory training

Sustained attention and rhythm control

Logic, pattern recognition and thinking games

Popular Tools

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Base64 Encode / Decode Convert text to and from Base64, full Unicode support. URL Encode / Decode Percent-encode or decode URL special characters. Text Hash Compute MD5 and SHA family digests. UUID Generator Batch-generate random v4 UUIDs. Password Strength Rate password strength and estimated crack time. JSON Formatter Prettify or minify JSON with validation. JSON to CSV Convert JSON arrays to downloadable CSV. Regex Tester Live matching with full group and flag support. Timestamp Converter Unix timestamps to dates, with timezones. Subnet Calculator Network, broadcast and host counts from CIDR. Word Count Characters, words, lines and reading time. QR Code Generator Turn URLs or text into downloadable QR codes.

Popular Games

10 games View all →

Reaction Time Test Brain Games Wait for the color change, then click to measure reflexes. Arrow Memory Challenge Brain Games Memorize the flashing arrow sequence and repeat it. Rhythm Trainer Brain Games Tap the spacebar with the beat and measure your timing stability.

Updated

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Dice Roller Roll multi-sided dice and view distribution. Coin Flip Flip once or many times with tallies. Random Picker Draw one or more entries from a list. Number to Chinese Convert amounts to Chinese capital numerals. Age & Day Counter Age, days lived, and next birthday countdown. Data Size Converter Precise KB, MB, GB, TB conversion. Weight Converter Kilograms, jin, pounds, ounces and more. Length Converter Metric and imperial length units. Temperature Converter Celsius, Fahrenheit, Kelvin, Rankine. Contrast Checker Check text contrast against WCAG rules. Color Picker & Converter Convert HEX, RGB, HSL and get palettes. Image Compressor Compress images locally, nothing uploaded.

About this site

This is a completely free collection of online tools and brain games. Every tool runs inside your own browser — nothing you paste ever leaves your device.

No sign-up, no pop-ups, no profiling. Open what you need, and closing the tab leaves nothing behind.

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