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Regex, CSS & Code Utilities

Test and debug regular expressions with live matches, and minify or beautify CSS and HTML in one click. These code utilities are built for quick, in-browser fixes while you work — no accounts, no uploads, no waiting.

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Guides for regex, css & code utilities

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Aug 28, 2026 · 2 min read The Complete Guide to Dates and Times for Developers How computers represent time — epoch timestamps, UTC and time zones, ISO 8601, and scheduling — with focused deep-dives and tools. Unix Timestamp Converter Aug 28, 2026 · 3 min read The Complete Guide to Regular Expressions Regex end to end — literals, metacharacters, character classes, quantifiers, anchors, groups, and flags — with focused deep-dives and a live tester. Regex Tester Aug 28, 2026 · 2 min read ISO 8601 & UTC: Date Formats and Time Zones Explained How to write dates that never get misread — the ISO 8601 format, what UTC and the Z suffix mean, time-zone offsets, and daylight-saving pitfalls. Unix Timestamp Converter Aug 28, 2026 · 2 min read Regex Character Classes, Quantifiers & Anchors The core building blocks of every regex — character classes and shorthands, greedy vs lazy quantifiers, and the anchors that pin a match to a position. Regex Tester Aug 28, 2026 · 2 min read Regex Groups, Backreferences & Lookarounds The advanced-but-everyday regex features — capturing and named groups, alternation, backreferences, and lookahead/lookbehind assertions. Regex Tester Aug 28, 2026 · 2 min read What Is Unix Time? Epoch, Seconds & the Year 2038 Problem Unix time explained — what the epoch is, why time is counted from 1970, seconds vs milliseconds, leap seconds, and the Year 2038 problem. Unix Timestamp Converter Aug 26, 2026 · 1 min read How to Convert Unix Timestamps Understand Unix time — seconds vs milliseconds, UTC vs local, and how to convert an epoch timestamp to a human date and back. Unix Timestamp Converter Aug 26, 2026 · 2 min read How to Read a Cron Expression Decode the five fields of a cron schedule — minute, hour, day, month, weekday — plus ranges, steps, lists, and the day-of-month/day-of-week rule. Cron Expression Parser Aug 9, 2026 · 2 min read HEX, RGB, HSL & CMYK: A Guide to Color Formats What HEX, RGB, HSL and CMYK mean, how they differ, and when to use each when working with color on the web. Color Converter Aug 9, 2026 · 1 min read CSS Minification: Why and How to Minify Your CSS What CSS minification does, how much it saves, when to minify vs beautify, and how it fits a fast-loading site. CSS Minifier & Beautifier Aug 9, 2026 · 2 min read How to Test and Debug Regular Expressions A practical approach to writing and debugging regex — flags, capture groups, common tokens, and how to test a pattern against real text. Regex Tester Aug 9, 2026 · 1 min read HTML Minification: Shrink Your HTML for Faster Loads What HTML minification removes, how much it saves, when to minify vs beautify, and how it helps page speed. HTML Minifier & Beautifier

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