Skip to content
FileKit
12 tools

Developer Tools

Format, minify, validate and convert code without leaving the browser tab. These developer tools handle the small transformations that interrupt a build, from prettifying a JSON payload to turning an SVG into a React component.

Code Diff Checker

Compare two pieces of code or text line by line with added, removed and unchanged lines marked clearly.

txt

Cron Expression Parser

Parse a five field cron expression into plain English and see the next run times computed in your local time zone.

txt

CSS Minifier

Strip comments and whitespace from CSS, collapse redundant semicolons, and keep strings and url values intact.

csscss

HTML Minifier

Collapse HTML whitespace and strip comments while preserving the exact content of pre, textarea, script and style elements.

htmlhtml

HTML to JSX Converter

Convert HTML markup to JSX with attribute renaming, inline style object conversion and self closing tag fixes.

htmljsx

JavaScript Minifier

Strip comments and unnecessary whitespace from JavaScript with a scanner that respects strings, template literals and regex literals.

jsjs

JSON Formatter

Pretty print JSON with a choice of indent width, an option to sort keys, and a precise line and column error when parsing fails.

jsonjson

JSON Validator

Validate JSON with a precise line and column error position, plus stats on depth, key count and document size.

json

Regex Tester

Test a regular expression live against your text, inspect capture groups and match indexes, and preview a replace.

txt

SQL Formatter

Format SELECT, INSERT, UPDATE, DELETE and JOIN statements with keyword uppercasing and clause based indentation.

sqlsql

SVG Optimizer

Strip comments, metadata and editor namespaces from an SVG, remove empty groups and round path precision.

svgsvg

SVG to React Component Converter

Paste or upload an SVG and get back a typed React component with camelCase props, forwarded refs and a memo option.

svgtsx

Why use browser based developer tools

Every developer keeps a mental list of the little utilities they reach for a dozen times a week. Pretty print this API response. Minify this stylesheet before pasting it into a CMS. Escape this string for a JSON config. Convert this icon into a component. These developer tools cover that list without an install step and without sending proprietary source code to a third party endpoint.

Running client side is not a marketing detail here, it is the whole point. Pasting an internal API response into a random online formatter is a data leak. Everything in this cluster parses and transforms in your own browser process, so the payload you paste never travels anywhere.

Frequently asked questions

Yes. Every tool in this category is free with no account, no trial and no daily limit. The tools run as JavaScript inside your own browser, so there is no server cost to pass on and no reason to meter usage.

No. Files are read directly from your device into browser memory, processed locally and written back out as a download. Nothing is transmitted, nothing is logged and nothing is stored after you close the tab.

There is no limit imposed by us. The practical ceiling is your own device memory, because the file has to fit in the browser tab while it is being processed. Most machines handle files of several hundred megabytes without trouble.

Current versions of Chrome, Edge, Firefox and Safari on desktop and mobile are all supported. Where a specific tool depends on a capability that a browser has not shipped yet, that tool says so on its own page before you select a file.