Tools
Free utilities for webdevs, sysadmins, and SEO teams. No signup required, no rate limits on most tools.
SEO Tools
Free, instant utilities for day-to-day SEO work. No signup required.
Meta tags & SERP preview
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SEO
Meta Tag Preview
See how any page looks on Google, Twitter, and Facebook. Catches missing/overlong title, description, Open Graph, and Twitter Card tags.
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SEO
Title Tag Length Checker
Check any page title character count and approximate Google pixel width. Flags missing, empty, too-short, too-long, and pixel-overflow titles.
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SEO
Meta Description Preview
Pull the meta description from any URL and render a Google SERP mockup. Flags missing, too-short, too-long, and title-duplicate descriptions.
Crawling & indexing
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SEO
Redirect Chain Checker
Trace every hop a URL takes. Catches loops, 302→permanents, HTTPS downgrades, meta refreshes, and slow chains.
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SEO
Canonical Tag Analyzer
Check any page's canonical tag: whether it exists, points to itself, uses an absolute URL, crosses domains, mismatches HTTP/HTTPS, or has a trailing slash conflict.
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SEO
Robots.txt Validator
Fetch any site's robots.txt, see per-agent rules, check AI crawler access (GPTBot, ClaudeBot, Google-Extended), and spot syntax errors.
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SEO
Sitemap.xml Validator (Extended)
Deep sitemap check: URL count, accessibility probe on 10 random URLs, mixed HTTP/HTTPS detection, >50 MB and >50k URL warnings.
Page structure
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SEO
Heading Hierarchy Analyzer
Analyze any page's H1-H6 structure: missing or multiple H1s, skipped levels, empty headings, overlong text, duplicates, and a visual heading tree.
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SEO
Image Alt Text Coverage
Parse all img tags on a page and report alt text coverage. Distinguishes missing alt, decorative (alt=), and content images.
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SEO
Schema.org Detector
Parse any page for JSON-LD structured data and microdata. Lists every schema type found and flags parse errors.
Developer Tools
Free dev utilities — encoders, formatters, validators, generators. Most run entirely in your browser.
Format & Validate
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DEV
JSON Formatter & Validator
Validate, format, minify, and query JSON. Pretty-print with 2 or 4-space indent. JSONPath query support. Runs entirely in your browser.
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DEV
HTML / XML Formatter
Pretty-print or minify HTML and XML. Auto-detects format. Catches mismatched tags and unclosed elements.
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DEV
YAML Formatter & Validator
Validate, format, and convert YAML to JSON. Shows parse errors with line and column. js-yaml under the hood.
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DEV
CSV ↔ JSON Converter
Convert CSV to JSON and back. Header-row detection, configurable delimiter, handles quoting and escaping.
Encoding
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DEV
Base64 Encoder / Decoder
Encode text or files to base64, decode base64 to text. Drag and drop images for data URLs. UTF-8 safe.
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DEV
URL Encoder / Decoder
Encode or decode URLs (encodeURIComponent). Parse mode shows scheme, host, path, query, and fragment.
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DEV
JWT Decoder & Verifier
Decode JWT header and payload, humanize iat/exp/nbf timestamps. Verify signatures: HS256/384/512, RS256/384/512, ES256/384.
Crypto & IDs
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DEV
Hash Generator (MD5 / SHA / HMAC)
Generate MD5, SHA-1, SHA-256, SHA-512 hashes from text or file. HMAC mode for webhook signature verification.
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DEV
UUID Generator (v1, v4, v7)
Generate UUID v4 (random), v1 (timestamp), or v7 (sortable). Bulk generation up to 100 at once.
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DEV
Password Generator
Generate cryptographically random passwords. Configurable length, character classes, entropy score, exclude ambiguous chars.
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DEV
Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal. Live update across all four bases.
Time
Utilities
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DEV
Diff Tool (Text & JSON)
Compare two texts side by side with line and character-level highlights. JSON-aware mode normalizes object key order.
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DEV
Regex Tester
Test regular expressions against multiline text. Live match highlighting, capture groups, replacement preview, all flags.
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DEV
Markdown Preview
Live-render Markdown to HTML side by side. GitHub-flavored Markdown. Download the rendered HTML.
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DEV
QR Code Generator
Generate QR codes from any text or URL. Customizable size, error correction level, foreground and background colors. PNG and SVG download.
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DEV
Case Converter
Convert text between camelCase, snake_case, PascalCase, kebab-case, CONSTANT_CASE, Sentence case, and more. Live update.
Network & DNS
DNS, IP, and HTTP inspection tools for admins and developers.
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NET
DNS Lookup
Look up DNS records for any domain: A, AAAA, CNAME, MX, TXT, NS, SOA, CAA with TTL values. Optionally specify a nameserver.
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NET
HTTP Headers Viewer
Inspect HTTP request and response headers for any URL. Configurable method and User-Agent. See the full redirect chain.
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NET
IP / ASN Lookup
Look up IP geolocation, ASN, organization, and reverse DNS for IPv4 or IPv6 addresses. Bulk mode supports up to 100 IPs.
Accessibility
WCAG and APCA tools for designers and front-end developers.
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