All tools

Generate v4 UUIDs in batch.

Check whether strings are valid UUIDs.

Inspect JWT header and payload (signature not verified).

Compute SHA-1, SHA-256, and SHA-512 digests.

Generate strong passwords with customizable length and character types.

Test patterns live with capture groups.

Turn cron expressions into human-readable schedules.

Beautify or minify HTML markup.

Beautify or minify XML documents.

Format or compact SQL (dialect in secondary field).

Beautify or minify JavaScript source.

Beautify or minify CSS stylesheets.

Encode or decode HTML entities.

Convert numbers between binary, octal, decimal, and hex.

Compute HMAC with a secret in the secondary input.

Convert among HEX, RGB, and HSL.

Validate OpenAPI 2.x/3.x structure (JSON or YAML).

Generate TypeScript interfaces from JSON.

Generate .gitignore templates by stack.

Parse or validate .env key/value files.

Bump or compare semantic versions.

Convert between CSV and JSON.

Merge multiple PDF files into one.

Split PDFs by page ranges.

Reduce PDF size while keeping readability.

Build SEO and Open Graph meta tags.

Create robots.txt with optional sitemap URL.

Build sitemap.xml from a list of URLs.

Export an Excel sheet to CSV on the server.

Compute MD5, SHA-1, or SHA-256 for uploaded files.

Compress JPG, PNG, and WebP images.

Resize images to target dimensions.

Create QR codes from text or URLs.

Read QR content from an image.

Convert Google Authenticator migration payloads to standard otpauth entries locally.

Optimize SVG and convert to PNG/JPG — not a full vector editor.

Convert images between JPG, PNG, WebP, and AVIF.

Create a 32×32 PNG favicon from an image.

Lightweight Markdown and HTML conversion.

Compare two texts with highlighted changes.

Turn short text into multi-font ASCII banners for README and CLI.

Switch letter case styles in bulk.

Generate placeholder paragraphs.

Count words, characters, lines, and sentences.

Sort lines, remove duplicates, or both.

Turn titles into URL-safe slugs.

Estimate reading time from word count and WPM.

Convert UTF-8 text to and from Base64.

Encode or decode URLs and query strings safely.

Convert Unix time and ISO-8601 with time zones.

Debug API requests with method, auth, headers, query, and body.

Validate international bank account numbers (MOD-97).

Luhn check for test card numbers only — not for live payments.

Normalize phone digits to E.164-style output.

Browse and filter IANA time zones with current offsets.

Convert length, weight, and temperature units.