Free Online Broken Link Checker (404 Dead Links)

Website Uptime & Status Checker

Check if a website is down or responding slowly from multiple global locations.

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REST API Probe & Tester

Send GET, POST, PUT, DELETE requests with custom headers and JSON payloads.

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Network Latency & TTFB Benchmark

Measure DNS lookup, TCP handshake, TLS negotiation, and First Byte arrival times.

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Keyword & Content Presence Monitor

Verify if specific keywords, phrases, or HTML strings appear in live website content.

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Cron Job Heartbeat & Dead Man's Snitch

Monitor background workers, scheduled cron jobs, and backup pipelines.

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Global 36-Server Reachability Test

Concurrently probe your domain from 36 server nodes across 12 countries in ~1.5 seconds.

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DNS Record Lookup & Query

Query A, AAAA, MX, TXT, CNAME, NS, SOA, and PTR records for any domain.

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Global DNS Propagation Checker

Check DNS record resolution across global public DNS providers and root servers.

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Reverse DNS (PTR) Lookup

Resolve an IPv4 or IPv6 address back to its associated hostname and domain.

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DNSSEC Validation Checker

Verify DNS Security Extensions (DNSSEC), DS records, DNSKEY, and RRSIG signatures.

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Domain WHOIS & Expiration Tracker

Check domain registration age, renewal deadline, registrar, and WHOIS status.

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Email Security Suite (SPF, DKIM, DMARC)

Audit email authentication records to prevent domain spoofing and phishing.

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SSL/TLS Certificate Inspector

Verify certificate validity, days remaining, cipher suites, issuer, and SAN coverage.

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HTTP Security Headers Analyzer

Evaluate HSTS, CSP, X-Frame-Options, X-Content-Type-Options, and Referrer-Policy.

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TCP Port & Socket Availability Checker

Test whether network ports (80, 443, 22, 21, 3306, 8080) are open, filtered, or closed.

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IP Geolocation, Reverse DNS & ASN

Discover physical location, ISP, Autonomous System Number, and network owner.

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HTTP Redirect Checker & URL Unshortener

Trace 301, 302, 307, 308 redirect loops, affiliate links, and shortened URLs.

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Meta Tags & Social Graph Previewer

Preview OpenGraph (Facebook/LinkedIn), 𝕏/Twitter Cards, and Google search snippets.

seo

Robots.txt Parser & Bot Simulator

Test crawl access for Googlebot, Bingbot, GPTBot, and custom search crawlers.

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XML Sitemap Parser & Health Checker

Parse sitemap indexes, extract URLs, verify lastmod dates, and check response codes.

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Favicon & Web App Icon Explorer

Extract standard favicons, Apple Touch icons, Android PWA manifests, and SVG vectors.

seo

Readability & Content Length Extractor

Extract main article text, calculate reading time, word count, and Flesch-Kincaid score.

seo

Broken Links Crawler & Internal Health

Scan webpage hyperlinks to detect 404 dead links, server errors, and bad anchors.

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JSON Formatter, Validator & Minifier

Format messy JSON with 2-space indentation, validate syntax, and compress into 1 line.

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JWT Token Decoder & Claims Inspector

Decode header algorithms, payload claims, expiration timestamps, and issuer details.

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Cryptographic Hash Generator

Generate secure cryptographic message digests and HMAC signatures instantly.

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Base64 Encoder & Decoder

Encode and decode standard and URL-safe Base64 strings and image data URIs.

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UUID / GUID Generator (v4)

Generate batches of RFC 4122 v4 Universally Unique Identifiers with custom formatting.

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Unix Timestamp & Epoch Converter

Convert epoch seconds and milliseconds to human-readable UTC and local date formats.

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URL Encoder & Decoder

Safely encode and decode query parameters, special characters, and percent codes.

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User-Agent String Parser

Parse browser family, rendering engine, OS version, device brand, and bot signatures.

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CSV to JSON & JSON to CSV Converter

Convert tabular spreadsheet data to JSON arrays and structured JSON to clean CSV files.

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Regular Expression (RegEx) Tester

Test patterns, flags (g, i, m, s), capture groups, and match highlighting.

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Secure Password & Passphrase Generator

Generate cryptographically secure random passwords with entropy calculations.

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QR Code Generator & Styler

Generate clean, scannable QR codes for URLs, WiFi credentials, and text payloads.

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Magic Byte & File Type Identifier

Detect real file types, spoofed extensions, and MIME types from binary headers.

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Multi-Hash File Checksum Verifier

Verify file integrity, detect tampering, and calculate cryptographic checksums.

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Smart Image Compressor & Size Reducer

Compress JPEG, PNG, and WebP images by up to 90% without visible loss of quality.

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Multi-Format Image Converter (WebP, PNG, JPG)

Convert images between modern WebP, lossless PNG, and compressed JPEG formats.

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Dimension Resizer & Aspect Scaler

Resize image width and height in pixels or scale by percentage while locking aspect ratio.

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Custom Drag & Aspect Ratio Image Cropper

Crop photos with an interactive on-canvas drag box, rule-of-thirds grid, and fine-tuning sliders.

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EXIF & Privacy Metadata Stripper

Strip GPS coordinates, camera serial numbers, date taken, and author info from photos.

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Dominant Color Palette Extractor

Extract harmonious color palettes, HEX codes, and RGB values from any image.

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SVG Vector Silhouette Tracing

Convert raster logos and icons into infinitely scalable SVG vector silhouettes.

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Broken Links Crawler & Internal Health Auditor

Single-Page Broken Link Scanner

About the Broken Links Crawler & Internal Health

How to Use

Understanding Results

Frequently Asked Questions

Do broken links hurt SEO?

Related SEO & Webmaster Utilities