UltraConvert
11 tools

Converters

JSON formatters, number base converters, color converters, timestamp tools. All tools run 100% in your browser — no uploads, no accounts needed.

Available Converters

Color Converter

Convert between HEX, RGB, and HSL color formats with bidirectional editing — change any value and all others update instantly. The native browser color picker provides visual selection, while precise numeric inputs enable exact color specification. Copy CSS-ready formats directly for web development and design work.

Instant • Private

CSV ↔ JSON Converter

Convert between CSV and JSON formats for data interchange and processing. CSV to JSON creates arrays of objects using the first row as keys. JSON to CSV generates properly formatted CSV with automatic headers. Full RFC 4180 compliance including quoted fields, embedded commas, newlines within cells, and custom delimiters.

Instant • Private

Data Size Converter

Convert between data storage and transfer units for both decimal (SI) and binary (IEC) standards. Understand the difference between gigabytes (GB, 10^9) and gibibytes (GiB, 2^30) that causes confusion with hard drive sizes. Live grid shows your value in bits, bytes, and all common prefixed units simultaneously.

Instant • Private

JSON Formatter & Validator

Transform JSON between pretty-printed, minified, and validated formats instantly. Perfect for reading complex API responses, optimizing JSON for transmission, or debugging syntax errors. Live validation with line and column error indicators helps you fix malformed JSON quickly. The native browser parser ensures standards-compliant processing.

Instant • Private

Length Converter

Convert between all common length and distance units in real time. Type a value in any unit and see instant conversion to millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and more. The multi-unit grid shows all values simultaneously with one-click copy for any measurement. Uses exact international yard definition (0.9144 m) for precise conversions.

Instant • Private

Number Base Converter

Convert any integer between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Backed by JavaScript's BigInt for arbitrarily large integers — handle numbers far beyond JavaScript's safe-integer limit of 9,007,199,254,740,991. Bidirectional editing means changing any field instantly updates all others.

Instant • Private

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, and Rankine temperature scales in real time. Type any value and all others update instantly. Includes common reference points (water freezing/boiling, body temperature, absolute zero) for quick orientation. Essential for cooking, science, travel, and engineering.

Instant • Private

Unix Timestamp Converter

Convert between Unix epoch timestamps and human-readable dates instantly. Auto-detects whether your input is in seconds or milliseconds based on magnitude. Outputs multiple formats including Unix seconds, Unix milliseconds, ISO 8601 (UTC and local), human-readable strings, and relative time calculations. The "Use current time" shortcut lets you work with the present moment.

Instant • Private

Weight Converter

Convert between all common weight and mass units instantly. Enter a value in any unit — kilograms, pounds, ounces, stone, grams, milligrams, tonnes — and see simultaneous conversion to every other unit. The live grid display shows all values at once with one-click copy. Includes both US (short) and UK (long) tons, plus stone-and-pounds breakdown popular in the UK.

Instant • Private

XML Formatter

Format XML documents for readability or strip whitespace for efficient transmission. The native browser XML parser ensures fast, standards-compliant processing with detailed error reporting including line and column information. Handles all XML features including namespaces, CDATA sections, comments, and processing instructions.

Instant • Private

YAML ↔ JSON Converter

Convert between YAML and JSON in either direction instantly. Built on js-yaml for full YAML 1.2 specification support including anchors, aliases, multi-line strings, and complex nested structures. Essential for DevOps work with Kubernetes manifests, GitHub Actions workflows, OpenAPI specifications, and Docker Compose files.

Instant • Private

About Converters

Our converters are designed to handle your files with complete privacy. Unlike online services that upload your documents to remote servers for processing, all our tools run entirely within your browser using WebAssembly technology. This means your sensitive files — whether they're financial documents, personal records, or confidential business materials — never leave your device.

Each tool is optimized for speed and reliability. We use industry-standard libraries like MuPDF for PDF operations, compiled to run at native speeds in your browser. There's no queue, no waiting, and no limits on file size beyond what your device can handle.

Common questions

Are these tools really free?
Yes, all tools are completely free to use. There are no hidden fees, no subscription tiers, and no feature limitations. We believe useful tools should be accessible to everyone.
Is there a file size limit?
There's no artificial limit — you can process files as large as your device's memory allows. We've tested with files up to 500MB successfully. For extremely large files, make sure you have sufficient free RAM available.
Do I need to create an account?
No account or registration is required. Just open the tool, drop your files, and process them. We don't collect email addresses or personal information. Bookmark any tool for quick access in the future.