Fast Text Format Tools
The ultimate collection of lightning-fast utilities to format, convert, and streamline your workflow.
Favorites
Recently Used
Recently Added
Text & Compare
Case & Converters
Convert string cases, URL encode, and decode Base64 instantly.
Encoder / Decoder
Encode and decode various formats like URL, Base64, and HTML entities.
List Sorter & Deduplicator
Instantly sort text arrays alphabetically, numerically, or by length, and strip out duplicate lines.
Regex Replacer
Execute regular expressions, view live matches, and use cheat sheets.
Text Diff
Compare two text blocks side-by-side to highlight differences.
Text Statistics
Count words, characters, sentences, estimate reading time, and check keyword density.
Translator
Instantly translate text between dozens of languages.
Code & Formatting
Base64 to File
Decode Base64 strings or Data URIs back into downloadable files (images, PDFs, documents, audio) with instant live preview.
Code Beautifier
Beautify, validate, and minify your JSON, JavaScript, CSS, and HTML code into clean, readable syntax.
CSS Format
Format, beautify, validate, and minify CSS code with custom indentation.
CSS Visual Generators
Visually generate and export CSS code for Box Shadows, Gradients, Flexbox, and Grid layouts.
CSV to JSON/SQL
Convert CSV data to JSON arrays or SQL INSERT statements.
cURL to Fetch
Easily convert cURL commands into JavaScript Fetch API code.
HTML / XML
Beautify, minify, and clean up messy code instantly.
HTML to JSX
Client-side tool to transform HTML tags/attributes into React-compatible JSX.
HTML to Tailwind CSS
Convert standard inline styles and CSS declarations into Tailwind CSS utility classes with live preview.
JS Obfuscator
Transform readable JavaScript code into unreadable, minified code to protect logic.
JSON to Code
Convert JSON objects into typed models for various languages.
JSON Tree Viewer
Visually inspect, expand, collapse, search, and filter complex JSON payloads with path inspection.
Markdown
Write raw markdown with a live HTML preview.
Source Map Viewer
Client-side tool to upload a .map file and de-minify stack traces.
SQL Formatter
Beautify and format messy SQL queries.
String Escape & Unescape
Safely escape (and unescape) quotes, backslashes, and newlines for use in JSON strings, SQL queries, HTML, and Java/C#.
SVG Optimizer
Minify and clean raw SVG code.
SVG to PNG/WEBP
Client-side tool utilizing an HTML canvas to rasterize SVG code or files into downloadable images.
XML Utilities
Format and minify XML strings.
YAML <-> JSON
Instantly convert between YAML and JSON.
Data & Crypto
Bcrypt Hash
Generate and verify Bcrypt passwords locally.
Epoch Time
Convert timestamps to human-readable dates.
Hash Generator
Compute MD5, SHA-1, SHA-256, and SHA-512 cryptographic hashes.
JWT Decoder
Safely parse JSON Web Tokens into formatted Header and Payload data.
HMAC Generator
Compute and verify cryptographic HMAC signatures using SHA-256, SHA-512, MD5, and secret keys.
Generators & Utilities
ASCII Art
Generate large ASCII art text banners.
Barcode Generator
Client-side tool using a canvas to generate linear barcodes (UPC, EAN, Code39) from text.
CHMOD Calc
Calculate Linux file permissions easily.
Color Contrast
Check WCAG color contrast accessibility.
Color Format
Instantly convert HEX, RGB, and HSL color codes.
Cron Decoder
Translate cron schedules into human-readable text.
Favicon Generator
Convert standard images into universally compatible .ico files and generate standard web app icon sizes.
Image Base64
Convert image files into Base64 Data URI strings and CSS background-image properties.
Image Compressor
Compress and optimize JPEG, PNG, WEBP, and AVIF images locally in your browser.
Markdown Table Generator
A visual grid editor that allows users to easily add rows/columns and instantly outputs perfectly formatted Markdown table syntax.
Meta Tag & Open Graph Generator
Generate and visually preview SEO meta tags, Twitter Cards, and Facebook Open Graph tags.
Mock Data Generator
Generate hundreds of rows of fake test data (names, emails, addresses, dates, credit cards) and export it as CSV, JSON, or SQL INSERT statements for database testing.
Password Gen
Create strong, secure passwords using cryptographic algorithms.
PDF Toolkit
Merge, split, extract, rotate, and reorder PDF pages 100% locally in your browser.
Placeholder Text
Create random placeholder text for UI mockups.
QR Code
Create scalable, scannable QR codes from text or URLs.
Regex Tester & Builder
Test regular expressions with real-time match & capture group highlighting, syntax explanation breakdown, and multi-string test modes.
Robots.txt Generator
Build valid robots.txt rules, crawler directives, and block AI scrapers.
UUID / GUID
Instantly generate universally unique identifiers (v4).
XML Sitemap Generator
Construct valid XML sitemaps with custom URLs, change frequencies, and priorities for search engines.
Finance & Units
Currency Converter
Calculate global exchange rates in real-time.
Unit Converter
Instantly convert length, weight, temperature, and data storage.
Networking
DNS Lookup
Check DNS records in real-time.
HTTP Headers Viewer
View HTTP request headers sent by your browser.
Internet Speed Test
Test your download and upload connection speed.
IP Lookup
Look up IP addresses and geolocation data.
MAC Vendor Lookup
Identify hardware vendors from MAC addresses.
RDAP Lookup
Lookup domain and IP registration data, registrar, nameservers, and DNSSEC status via RDAP.
Redirect & Link Trace
Unmask shortened URLs and trace full HTTP 301/302 redirect chains to their final destination.
SSL Certificate Inspector
Inspect live SSL/TLS certificates, issuer chains, expiration countdowns, SAN domains, and fingerprints for any domain.
Subnet Calculator
Calculate CIDR network masks and IP ranges.
URL Parser
Extract and build URL query strings easily.
User-Agent Parser
Extract OS and browser info from User-Agent strings.
Webhook Tester
Send, test, and debug webhook deliveries with custom headers, HMAC signatures, and live response inspection.
Regex Tester & Builder
Test regular expressions with real-time match & capture group highlighting, syntax explanation breakdown, and multi-string test modes.
| # | Full Match | Groups | Index | Length |
|---|---|---|---|---|
| No matches found in the test text. | ||||
How to Use
Enter a regular expression pattern and toggle flags (Global, Case-Insensitive, Multiline, DotAll, Unicode). In Single Text mode, type sample text to inspect visual match and capture group highlights and syntax breakdowns. In Multi-String mode, test multiple individual string inputs simultaneously against your pattern.
Frequently Asked Questions
What is the Regex Tester & Builder?
The Regex Tester & Builder is an interactive developer tool designed to test, debug, and explain regular expressions with visual match highlighting, capture group extraction, and multi-string validation.
How are capture groups visually highlighted?
Each numbered or named capture group within a match is rendered in a distinct high-contrast color badge with tooltips displaying group names, indices, and character offsets.
What regex flags are supported?
The tester supports standard ECMAScript JavaScript regex flags: Global (g), Case-Insensitive (i), Multiline (m), DotAll (s, where dot matches newlines), and Unicode (u).
How does the syntax explanation feature work?
The syntax engine tokenizes your regular expression pattern and breaks down anchors, character classes, quantifiers, lookaheads, and capture groups into plain English explanations.
What is Multi-String Test mode?
Multi-String mode allows you to create a list of test cases (such as positive and negative validation examples) and instantly see green PASS or red FAIL indicator badges for each row.
Can I test named capture groups?
Yes. Named groups formatted like (?<name>pattern) are fully supported and displayed in the capture groups table with their custom identifier names.
Are catastrophic backtracking patterns handled safely?
Regex execution is executed client-side with safety timeouts to prevent browser lockups from uncontrolled exponential backtracking expressions.
Does this tool support ready-to-use pattern presets?
Yes. Presets for common tasks such as email addresses, URLs, IPv4 addresses, dates, phone numbers, and UUIDs are available with a single click.
Is any of my test data sent over the network?
No. All regex testing, token parsing, and string matches are evaluated 100% locally in your web browser. No queries or strings leave your device.
How does this differ from the Regex Replacer tool?
The Regex Replacer specializes in find-and-replace text transformations, while the Regex Tester & Builder focuses on visual inspection, capture groups, syntax explanations, and automated unit-test validation.
No results found
Try adjusting your search terms.