Daily-use developer utilities: regex testing with match highlighting, UUID generation (v4 random + v7 time-ordered), Unix↔ISO timestamp conversion, cron expression building and parsing, cURL-to-code translation for JavaScript and Python, JSON-to-TypeScript and JSON-to-Python type inference, SQL formatting across six dialects, and Prettier-based code beautification + Terser-based minification for JS / CSS. All thirteen tools run in your browser, so snippets, credentials, and proprietary code stay on your machine.
For **regex work**, Regex Tester uses the same engine as your JavaScript runtime — prototype here, then copy into code. For **IDs**, use UUID Generator (v4 for random, v7 for time-ordered at database scale) or Random Number for non-UUID formats. **Timestamp** handles Unix↔ISO; Cron Generator + Cron Parser build and explain cron expressions. For converting a **cURL** command into code, cURL to Code emits fetch / axios / Python requests. For **type inference** from JSON samples, JSON to TS emits TypeScript interfaces; JSON to Python emits TypedDict. For **formatting**, Code Beautify handles 8 languages; SQL Formatter handles 6 SQL dialects specifically.
Which JavaScript regex engine does Regex Tester use?
The browser's built-in RegExp — the same engine your application code will use at runtime. For language-specific engines (Python, PCRE, Go), behaviours differ on edge cases like lookbehind and Unicode categories — prototype here first, then verify in your target language.
Which UUID version should I pick?
v4 (random) is the standard for most IDs. v7 is RFC-9562 time-ordered: IDs sort chronologically, which dramatically improves B-tree index locality in high-write databases. Neither is "better" — pick based on whether sort-by-creation-time is useful.
Does Code Beautify run Prettier server-side?
No — it uses Prettier's standalone browser build. Language parsers are lazy-loaded on demand (per-language), so the first format takes a second but subsequent runs in the same session are instant.
How good is the JSON → TypeScript inference?
It handles nested objects, arrays of objects (merged into a single interface with optional fields for keys that vary across samples), and primitive types. For production-grade schema work (validation, custom types), use a schema library like Zod — this tool emits types, not runtime validators.
Are any of these tools uploading my files?
No. Every tool in this category runs entirely in your browser. Files you drop in are processed locally, never sent to a server, and discarded when you leave the page.