Free Online Converters

ToolFlip's converters handle four distinct domains where format translation comes up constantly in design, development, and data work: color codes, physical units, image dimensions, and structured data. Every tool runs in your browser — nothing is uploaded, no account is needed, and there are no request limits.

Color conversion. The Hex to RGB converter works with all three CSS color formats — hexadecimal, RGB, and HSL — and updates all three simultaneously as you type. Enter #3B82F6 and you immediately see rgb(59, 130, 246) and hsl(217, 91%, 60%) alongside a live color swatch. This is the workflow for front-end developers translating a brand color from a Figma spec into a Tailwind config, or for designers verifying that a hex value from a screenshot matches the hue they expect. The tool parses shorthand hex (#38F), handles both uppercase and lowercase input, and follows the CSS Color Level 4 parsing rules — so the values it produces can be pasted directly into a stylesheet without adjustment.

Unit conversion. The unit converter covers eight measurement categories: Length, Weight, Temperature, Volume, Area, Speed, Data, and Time. That covers the conversions that come up in everyday technical work — converting an API response from meters per second to miles per hour, checking a package weight in pounds before shipping internationally, or validating an image file size against a storage quota using the correct SI or IEC prefix. Temperature conversion uses the exact formulas from NIST Special Publication 811: °C to °F is (°C × 9/5) + 32, and Kelvin is always °C + 273.15. Data units use both SI prefixes (1 MB = 1,000,000 bytes) and IEC binary prefixes (1 MiB = 1,048,576 bytes), so you can match whichever convention the operating system or spec document uses.

Aspect ratio calculation. The aspect ratio calculator reduces any width × height pair to its simplest integer ratio using the Euclidean GCD algorithm — 1920 × 1080 becomes 16:9, 2560 × 1440 becomes 16:9, and 1080 × 1920 becomes 9:16 for portrait video. It also works in reverse: enter a target ratio and one known dimension to calculate the missing side. Preset buttons cover the ratios you reach for most often — 16:9 (widescreen HD), 4:3 (classic TV and presentation slides), 1:1 (square social posts), 21:9 (ultrawide cinema), and 9:16 (vertical Reels and Shorts). The output is exactly what you would put in a CSS aspect-ratio property or a video export dialog, without doing the GCD math by hand.

Data format conversion. The JSON to CSV converter takes a JSON array of objects — the standard shape returned by REST APIs and database export endpoints — and produces a CSV file with a header row derived from the first object's keys. You can choose comma, tab, or semicolon as the delimiter. Semicolon is the correct default for Excel on European locales where the comma is reserved as the decimal separator; tab-delimited output pastes cleanly into Google Sheets without needing a text import wizard. Nested objects and arrays are serialized as JSON strings so no data is silently dropped. The download button produces a .csv file with the correct MIME type (text/csv) so your browser or OS handles it correctly.

Taken together, these four tools cover the format conversions that come up repeatedly in web development, data analysis, and design work. Each one is single-purpose and fast — paste or type a value, get the answer, copy it out. No configuration screens, no export wizards, no rate limits.