All-In-One SEO & Social Preview Studio
Preview a title, description and image as a Google result and as Facebook, X and LinkedIn...
Tools for Developers, SEO & the Web
Free tools for everyday web tasks: format code, convert and compress images, work with PDFs, check DNS and HTTP headers, and generate SEO markup. They do real work on real files, and you do not need an account.
84 Tools
7 Categories
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Quick Access
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SEO Tools
Checks and generators for technical SEO: meta tags, canonical URLs, Open Graph, sitemaps and robots.txt, plus previews of how a page may look in search and social. They check what is on the page. They do not predict rankings.
15 tools
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Canonical URL Checker & Validator
Check a page's canonical tag: missing, self-referencing, pointing to another domain, duplicated, or set in an...
FAQ Schema Generator (JSON-LD)
Add questions and answers and get FAQPage JSON-LD markup to paste into your page. Note that...
Google Index & Crawlability Checker
Check a URL for common indexing blockers: status code, noindex, canonical and robots.txt. A diagnostic, not...
Google SERP Snippet Preview Tool
Type a title, URL and description to see a mock Google result on desktop and mobile,...
Keyword Density & Frequency Analyzer
Paste text to count words, count how often a keyword appears, and see its density and...
Moz Domain & Page Authority Checker
Look up Moz's Domain Authority, Page Authority and Spam Score for a URL through the Moz...
On-Page Broken Link Checker
Check the first 12 links on a single page for 404s and errors using HEAD requests....
On-Page Meta Tag Analyzer
Fetch a URL and check its title and description length, robots and canonical tags, viewport and...
Open Graph & Social Card Checker
Fetch a page and read its Open Graph and Twitter Card tags, with mock previews for...
Open Graph & Social Meta Generator
Write Open Graph and Twitter Card meta tags for a page: title, description, URL, image, type...
Robots.txt Checker & Syntax Validator
Fetch a site's robots.txt, list its rules and sitemap lines, and flag lines with no colon...
Robots.txt Generator
Create a robots.txt file with allow and disallow rules, a sitemap line and a rule for...
Webpage Size & Compression Checker
Measure a page's HTML size, check Gzip or Brotli compression and see the server response time....
XML Sitemap Checker & Validator
Fetch an XML sitemap or sitemap index and check that it parses, count its URLs, see...
Developer Tools
Formatters, converters and decoders for everyday development work: JSON, HTML, CSS and JavaScript formatters, Base64, URL and JWT tools, hash and UUID generators, a regex tester and a few server checks. Most of these run in your browser, so what you paste does not leave the page.
21 tools
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Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to text, with UTF-8 handled correctly. Runs in...
Bulk Multiple URL Opener
Paste a list of web addresses, one per line, and open them all in new tabs...
CSS Formatter & Minifier
Format messy CSS into readable rules or minify it for a smaller file. Includes a live...
DNS Records Lookup
Look up the DNS records for a domain: A, AAAA, CNAME, MX, TXT, NS or SOA....
Hash Generator (MD5, SHA-256, SHA-512)
Hash any text and see MD5, SHA-1, SHA-256, SHA-384 and SHA-512 digests side by side. Runs...
HEX, RGB, HSL & CMYK Color Converter
Convert a color between HEX, RGB, HSL and CMYK with a live preview and color picker....
HTML Formatter & Minifier
Indent messy HTML so it is readable, or strip whitespace and comments to shrink it. Includes...
JavaScript Formatter & Minifier
Indent JavaScript, run a snippet in a sandboxed frame and see console output. The minifier is...
JSON Formatter & Beautifier
Paste JSON, format it with 2 or 4 spaces, minify it, or check it for errors....
JSON to JSON Schema Converter
Paste a sample JSON object and get a draft-07 or 2020-12 JSON Schema inferred from it....
JSON Validator & Syntax Linter
Check whether a piece of JSON is valid. See the parser's error message, and fix trailing...
JWT (JSON Web Token) Debugger & Decoder
Decode a JWT to see its header, payload claims and expiry time. It decodes only and...
Regular Expression (RegEx) Tester
Test a regular expression against sample text, with flags, match highlights and capture groups. Uses the...
Server Status & HTTP Reachability Checker
Check whether a site is reachable from this server: DNS resolution, TCP connection, HTTP response code...
SSL / TLS Certificate Checker
Connect to a host on port 443 and read its SSL/TLS certificate: issuer, valid dates, days...
Unix Timestamp Converter
Convert a Unix timestamp to UTC, local time and ISO 8601, or turn a date into...
URL Encoder & Decoder
Encode text so it is safe in a URL, or decode percent-encoded text. Uses the same...
UUID / GUID Generator (v4)
Generate random version 4 UUIDs, 1 to 50 at a time, with optional uppercase and no...
Web Hosting & Server Provider Checker
Find the likely hosting provider of a website from its IP address, network owner and reverse...
Website Technology Stack Detector
Detect the CMS, JavaScript frameworks, analytics and CDN a site uses from its public headers and...
What Is My User Agent?
See your browser's user agent string and what it says about your browser, version, operating system...
Network & DNS
Look up what a domain and a server are doing: DNS records, WHOIS and registration data, redirect chains, HTTP status codes and response headers. The lookups run from this server, not from your browser, so results can differ from what you see locally.
6 tools
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Domain Age Checker
Find out how old a domain is: creation date, expiry date and age, taken from RDAP...
Domain to IP Lookup
Resolve a domain to its public IPv4 and IPv6 addresses, with reverse DNS names where available....
HTTP Redirect Chain Checker
Follow a URL through its 301, 302, 307 and 308 redirects, hop by hop, up to...
HTTP Response Headers Checker
Fetch a URL and see its response headers grouped into security, caching, content, server and other....
HTTP Status Code Checker
Request a URL with GET or HEAD and see its HTTP status code, response time, content...
WHOIS / RDAP Domain Lookup
Look up a domain's registrar, creation and expiry dates, name servers and status codes through RDAP....
PDF Tools
Merge, split, rotate and convert PDFs, turn images or HTML into PDF, convert Office files, and password-protect or unlock a document. Some of these are simple edits and some convert between layouts, which is never perfect. Each tool page says what to expect.
17 tools
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Excel to PDF
Convert an Excel or CSV file to PDF with a choice of A4, A3, Letter or...
HTML to PDF
Convert pasted HTML and CSS to a PDF. The HTML is sanitized on the server, then...
Images to PDF (Batch)
Combine up to 10 JPG and PNG images into a single PDF, one image per A4...
JPG to PDF
Turn one or more JPG images into a PDF with each image centred on its own...
Merge PDF
Combine two to ten PDF files into a single document. Files are uploaded to the server,...
PDF Editor
Edit a PDF in your browser: add text, shapes, drawings and images, white out text, rotate...
PDF Page Extractor
Extract chosen pages or page ranges from a PDF into a new file. Uses the same...
PDF to Excel
Detect tables in a text-based PDF and write them to an Excel workbook, one sheet per...
PDF to PDF/A
Add PDF/A metadata and an sRGB output intent to a PDF. Best effort: the result may...
PDF to PowerPoint
Convert each PDF page into a PowerPoint slide with text boxes and images placed where they...
PDF to Word
Convert a text-based PDF into an editable Word document. It cannot read scanned PDFs, and complex...
PNG to PDF
Convert PNG images to a PDF with one image per A4 page. Transparent areas become white....
PPT to PDF
Convert a .pptx file to PDF. It is redrawn by a custom converter, not PowerPoint, so...
Protect PDF
Password-protect a PDF with AES-256 encryption and set permissions for printing, copying, annotating and changing it....
Rotate PDF
Rotate every page of a PDF by 90, 180 or 270 degrees and download the result....
Split PDF
Pick page numbers or ranges like 1-3, 5 and get a new PDF containing only those...
Unlock PDF
Remove password protection from a PDF when you know the password. It cannot crack or guess...
Image Tools
Convert images between JPG, PNG, WebP and AVIF, compress them, resize them and crop them. Images are processed on the server and kept only temporarily. Quality, transparency and file size behave differently in each format, and each tool page explains how.
20 tools
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AVIF Compressor
Re-encode an AVIF at a chosen quality, with before and after sizes. AVIF is encoded on...
AVIF to JPG Converter
Convert an AVIF to JPG in your browser with a quality slider. Transparent areas are filled...
AVIF to PNG Converter
Convert an AVIF to PNG in your browser with transparency kept, for editors and apps that...
Image Compressor (Universal)
Compress a JPG, PNG, WebP or AVIF with a quality slider and see the before and...
Image Cropper
Drag a crop area, choose a fixed aspect ratio or free selection, and export. Runs in...
Image Dimensions Checker
Pick an image to see its pixel width and height, aspect ratio, megapixels and file size....
Image Quality & Format Converter
Convert an image to JPG, PNG, WebP or AVIF, set the quality and optionally resize it....
Image Resizer
Resize a JPG, PNG, WebP or AVIF by width and height with an aspect ratio lock...
JPG Compressor
Shrink a JPG by re-saving it at a lower quality, in your browser. See the original...
JPG to AVIF Converter
Convert a JPG to AVIF with a quality slider. AVIF can be much smaller than JPG....
JPG to PNG Converter
Convert a JPG to PNG in your browser. Pixels are kept as they are, the file...
JPG to WebP Converter
Convert a JPG to WebP with a quality slider, in your browser. WebP files are usually...
PNG Compressor
Re-encode a PNG in your browser. PNG is lossless and has no quality setting there, so...
PNG to AVIF Converter
Convert a PNG to AVIF and keep transparency. AVIF is encoded on the server, so it...
PNG to JPG Converter
Convert a PNG to JPG in your browser with a quality slider. Transparent areas are filled...
PNG to WebP Converter
Convert a PNG to WebP in your browser and keep transparency. Useful for logos, screenshots and...
WebP Compressor
Re-save a WebP at a lower quality to cut its size, with before and after sizes...
WebP to AVIF Converter
Convert a WebP to AVIF with a quality slider. Gains vary, so check the size and...
WebP to JPG Converter
Convert a WebP to JPG in your browser with a quality slider. Transparent areas are filled...
WebP to PNG Converter
Convert a WebP to PNG in your browser and keep transparency. PNG is lossless but usually...
WordPress Tools
Tools made for WordPress. At the moment this is the WordPress theme detector, which reads a public site's source to guess which theme it uses.
1 tools
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WordPress Theme Detector
Find the active theme of a WordPress site from its public assets: theme name, style.css details,...
Generator Tools
Generators for markup you would otherwise write by hand: .htaccess redirect rules, JSON-LD schema, meta tags and clean URL slugs. They run in your browser. Read the output before you deploy it.
4 tools
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.htaccess 301 & 302 Redirect Generator
Turn a list of old and new URLs into Apache .htaccess redirect rules, using Redirect or...
Schema Markup Generator (JSON-LD)
Generate simple JSON-LD for Article, Person, Organization, LocalBusiness, Product, BreadcrumbList or FAQPage. Basic fields only. Review...
SEO Meta Tag Generator
Generate HTML head tags: charset, viewport, title, description, author, robots, plus basic Open Graph and Twitter...
URL Slug Generator
Convert a headline into a lowercase URL slug with a hyphen or underscore, optionally removing common...
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