WEBSITE HEALTH
HTTP Status Codes Explained: 200, 301, 404 and 500
Learn what HTTP status codes mean, including 200, 301, 302, 404, 500, 502 and 503, and how to fix website response problems.
Website Health Guides
Learn how HTTP status, redirects, headers, response time and website availability affect technical health and user trust.
Topics covered:
HTTP statusRedirectsSecurity headersWebsite status
20 articles
All Website Health guides
20 guides covering website health topics.
WEBSITE HEALTH
Using the Website Status Checker to Diagnose Downtime
Learn how to use a website status checker to diagnose downtime, redirects, 5xx errors, DNS problems, SSL failures, CDN issues and timeouts.
WEBSITE HEALTH
Fixing 502 Bad Gateway and 503 Service Unavailable Errors
Learn what 502 Bad Gateway and 503 Service Unavailable mean, why they happen, and how to troubleshoot CDN, origin, hosting and server issues.
WEBSITE HEALTH
Security Headers You Should Know
Learn the most important HTTP security headers, including CSP, HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy and Permissions-Policy.
WEBSITE HEALTH
Using an HTTP Header Checker to Audit Your Site
Learn how to use an HTTP Header Checker to audit response headers, security headers, cache rules, cookies, redirects, CDN behavior and website issues.
WEBSITE HEALTH
Referrer-Policy Header: Why It Matters
Learn what the Referrer-Policy header does, how it protects URL privacy, which policy value to use, and how it affects analytics and website security.
WEBSITE HEALTH
Content-Security-Policy (CSP): Setup and Common Mistakes
Learn what Content-Security-Policy does, how to set up CSP safely, common CSP directives, report-only testing and mistakes that can break websites.
WEBSITE HEALTH
How to Set Up Clean Redirects After Moving a Site
Learn how to set up clean 301 redirects after moving a site, avoid redirect chains and loops, preserve SEO traffic and test migration URLs.
WEBSITE HEALTH
WWW vs Non-WWW Redirects: SEO and Technical Best Practices
Learn how to choose www or non-www, set up clean 301 redirects, avoid duplicate hosts, fix redirect loops and keep SEO signals consistent.
WEBSITE HEALTH
Uptime Monitoring vs On-Demand Status Checks
Learn the difference between uptime monitoring and on-demand status checks, when to use each, and how to diagnose website downtime and reliability issues.
WEBSITE HEALTH
DNS vs CDN: Where the Problem Really Lies
Learn how to tell whether a website problem is caused by DNS, CDN cache, CDN SSL, proxy rules, origin server errors or hosting configuration.
WEBSITE HEALTH
Diagnosing Slow Website Response Times
Learn how to diagnose slow website response times by checking redirects, DNS, SSL, CDN cache, origin server, database, WordPress, assets and third-party scripts.
WEBSITE HEALTH
Mobile Performance: Measuring and Improving Responsiveness
Learn how to measure and improve mobile performance, responsiveness, Core Web Vitals, images, JavaScript, fonts, layout stability and mobile UX.
WEBSITE HEALTH
PageSpeed vs Response Time: Two Different Metrics
Learn the difference between PageSpeed and response time, how TTFB, Core Web Vitals, server speed, images, JavaScript and frontend rendering affect performance.
WEBSITE HEALTH
Implementing Browser Caching for Better Performance
Learn how browser caching works, how to use Cache-Control headers, what to cache, what not to cache, and how to avoid stale or private content issues.
WEBSITE HEALTH
HTTP/2 and HTTP/3: What They Mean for Your Site
Learn what HTTP/2 and HTTP/3 are, how they improve website delivery, how to check support, and why protocol upgrades do not replace caching and optimization.
WEBSITE HEALTH
Using Prefetch and Preconnect to Speed Up Loading
Learn how prefetch, preconnect, dns-prefetch and preload work, when to use each resource hint, and how to avoid common performance mistakes.
WEBSITE HEALTH
Rate Limiting and How It Affects API Calls
Learn what rate limiting is, what 429 Too Many Requests means, how Retry-After works, and how to handle API limits safely with backoff and caching.
WEBSITE HEALTH
Fixing Mixed Content Errors on WordPress
Learn how to fix WordPress mixed content errors after HTTPS migration by updating URLs, database content, themes, plugins, CDN settings and cache.
WEBSITE HEALTH
The SEO Impact of Too Many 404 Errors
Learn when 404 errors hurt SEO, which missing URLs to fix first, when to use 301 redirects, and how to handle sitemap, internal link and backlink 404s.
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