Write HTML and see a live preview rendered in a sandboxed iframe. Perfect for prototyping and testing.
Bidirectional YAML to JSON and JSON to YAML conversion with auto-format detection and real-time preview. Perfect for configuration files, API payloads, and data migration.
Countdown to a specific date and time with live days, hours, minutes, and seconds display. Perfect for event countdowns and deadlines.
Scan thousands of log files or codebase files for regex patterns (IPs, API keys, URLs) and extract or replace them. Visual builder for non-coders with live preview.
Reduces JPG, PNG, and WebP file sizes using smart compression with a side-by-side quality preview slider. Balance file size and visual quality visually — max 20MB per image. Perfect for web optimization, email attachments, and social media uploads.
Add professional headers and footers to every page of your PDF. Supports text, page numbers ({{page}}/{{total}}), dates, and custom alignment. Perfect for reports and official documents.
HTML Preview lets you write HTML and see a live preview rendered in a sandboxed iframe. Perfect for prototyping and testing.. Everything runs inside your browser — nothing is uploaded to a server. It works on any device with a modern web browser.
Write HTML and see a live preview rendered in a sandboxed iframe. Perfect for prototyping and testing. It's ideal for developers, designers, and anyone who needs to write html and see a live preview rendered in a sandboxed iframe without installing software or sending data to external servers.
Direct text entry, file upload, or URL-based input — depending on the tool. Paste or type your content directly into the provided editor area.
Yes. After the initial page load, HTML Preview runs entirely on your device with no internet connection needed. All processing is done locally.
Tools cover JavaScript, CSS, HTML, SQL, Python, JSON, XML, CSV, and more. Check individual tool descriptions for specifics.
No. All code processing — formatting, minification, conversion, hashing — runs locally in your browser.
Yes. Since processing is local, performance depends on your device. Most operations handle large files without issue.
Yes. SQL uses sql-formatter, JSON uses native JSON.parse, and other formatters follow widely adopted formatting rules.
Yes. All developer tools work fully offline after the initial page load.
Time Converter
Convert between time units including seconds, minutes, hours, days, weeks, months, and years with precise decimal results.
Diff Checker
Compares two input texts side-by-side, highlighting inserted, deleted, and changed lines with distinct background colors.
Regex Tester
Provides an interactive environment where users can write a regular expression pattern, test it against sample strings, and view real-time match.
JSON Formatter
Pretty-prints raw JSON with configurable indent width, key sorting, and bracket collapsing options while flagging syntax errors with exact.
JS Minifier
Strips comments, whitespace, and shortens local variable names in JavaScript source without altering execution semantics.
Base64 Encode/Decode
Encodes text or small files into Base64 strings and decodes them back with automatic MIME-type detection for binary safety.