11 tools, free
Developer tools
Format and compare JSON, convert CSV, encode text, test regex, generate UUIDs, convert timestamps and minify CSS or JavaScript. Tools run locally in your browser with no sign-up.
Showing all: 11 tools
Which tool do I need?
Start from what you want to do. These are the most common developer jobs and the tool that does each one best.
- Turn API records into spreadsheet dataConvert JSON records and CSV with quoted cells, a table preview and explicit type rules.
- Inspect an API responseValidate JSON and format it without changing number literals or key order.
- Find differences between two JSON payloadsCompare two JSON documents key-by-key with highlighted value additions, deletions and modifications.
- Test a search patternInspect highlighted matches and captures with a worker timeout.
- Encode or decode Base64 data stringsConvert raw text and UTF-8 strings into standard Base64 representation without transmitting credentials.
- Format query parameters or unescape URLsSafely encode URI components and query strings or restore human-readable encoded URLs.
- Escape HTML entities for markup or templatesConvert special characters like ampersands and angle brackets into HTML entity codes and back.
- Generate v4 unique identifiersBatch-generate cryptographically random UUIDs using browser crypto.getRandomValues().
- Convert Unix epoch times and readable datesTranslate between epoch seconds or milliseconds and UTC/local ISO dates in real time.
- Reduce a stylesheetMinify CSS while preserving important comments and keeping rule restructuring disabled.
- Reduce a JavaScript fileMinify scripts or ES modules without executing the code.
Why client-side processing matters for developer workflows
In-browser execution for code, keys and payloads
Developers routinely paste sensitive data into online utilities: authentication tokens, API payloads, database records, and proprietary configuration files. When online tools dispatch that data to remote servers for processing, it risks exposure across intermediate proxies, server logs, and persistence layers.
Every developer tool on FileConvertify runs locally inside your browser's JavaScript runtime or an isolated Web Worker. Parsers like CSSO and Terser execute directly on your device's CPU. No network requests are dispatched when you format JSON, minify code, or encode strings, keeping your configuration and testing data strictly within your browser tab.
Integer ID preservation
Standard JavaScript JSON.parse() can truncate 64-bit integer IDs (such as Twitter or Discord snowflakes). Our JSON formatter parses raw token streams to keep large numeric literals exact.
Isolated worker threads
Operations such as minifying large scripts or testing complex regular expressions run in background Web Workers with execution timeouts, keeping the interface responsive.
Zero server retention
Encoded strings, tokens, and query parameters exist only in temporary tab memory. Once you navigate away or close the page, all pasted data is wiped immediately.
Common questions
Frequently asked questions
Answers about privacy, browser execution limits, and format compatibility for our developer tools.