AI-first diagnostics
AI Engineer for Your Website
The Enterno.io AI engineer checks your site — HTTP headers, SSL, DNS, speed — finds problems and writes a clear fix spec. 10 free monitors, no card required.
AI finds the problem — and writes the fix spec
Example report: the scan on the left, a ready-to-hand developer spec on the right.
Scanning example.com
67%
- HTTPS✓
- Content-Security-Policy✗
- Caching!
- DNS & MX✓
- Speed (LCP, TTFB)
32 of 48 checks done…
Problem found
Missing Content Security Policy (CSP)
The site does not send a Content-Security-Policy header. This raises the risk of XSS attacks and injections.
Ready spec for the developer
add_header Content-Security-Policy "
default-src 'self';
script-src 'self';
style-src 'self';
object-src 'none';
base-uri 'self';
frame-ancestors 'none';
" always;The spec is generated by AI from the detected problem and security best practices. Illustrative example.
How It Works
Three simple steps to a full analysis
01
Check
68+ tools scan your site in seconds
02
AI diagnosis
AI finds problems and explains the causes
03
Ready spec
Copy the instructions and hand them to a developer
All Tools
Comprehensive analysis and monitoring for your website
Website Analysis
12Domain & DNS
10Network
8Security & Email
11Why enterno.io
824.2K+
Checks Performed
386+
Active Monitors
18.9K+
API Requests
68+
Free Tools
01
Free
All basic tools available without registration or limits
02
Fast
Results in seconds. Servers in Russia — minimal latency
03
API Access
REST API to automate checks and integrate into your projects
04
24/7 Monitoring
Telegram and email alerts for site outages or SSL expiration
05
Telegram alerts
Instant notifications on outages, SSL expiry and DNS problems
06
Status pages
Public status pages for your services and clients
Articles & Guides
Useful resources on web development and administration
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Simple, transparent pricing
Start free. Upgrade when you need more control.
What our users say
Switched from UptimeRobot to Enterno — faster monitoring, better UI, and everything in Russian. Now tracking 30+ client sites.
Simple, clear API. Integrated checks into CI/CD in an hour — now every deploy automatically verifies SSL and security headers.
Perfect tool for freelancers. Free plan covers my needs, and I send PDF reports to clients as-is.
SSL Encrypted
Hosted in Russia
GDPR / 152-FZ Compliant
99.5% target availability
HTTP Headers Analysis Tool
Check HTTP response headers, status codes, redirect chains, server timing, and security headers for any website. Our tool sends a real request from a server in Russia and shows the complete response including all headers, cookies, and performance metrics. Use it to debug caching, security configuration, CORS, and content delivery.
Frequently Asked Questions
What are HTTP headers?
HTTP headers are metadata sent between a browser and a server with every request and response. They control caching, security, content type, redirects, and many other aspects of how a web page is delivered.
How to check HTTP headers of a website?
Enter any URL in the form above and click Check. The tool will show all response headers, status codes, redirects, cookies, and a security header analysis.
What security headers should every site have?
Key security headers include Content-Security-Policy, Strict-Transport-Security (HSTS), X-Content-Type-Options, X-Frame-Options, and Permissions-Policy. They protect against XSS, clickjacking, and other common attacks.
What does the status code mean in HTTP response?
HTTP status codes indicate the result of a request: 2xx means success, 3xx means redirection, 4xx means client error (e.g., 404 Not Found), and 5xx means server error. The exact code helps diagnose issues.
Is this tool free?
Yes, the HTTP header checker is completely free with no limits on the number of checks. You can also create a free account to save your check history and access additional features.
What is HSTS and why is it important?
HSTS (HTTP Strict Transport Security) is a header that tells the browser to always use HTTPS for a given site. It prevents protocol downgrade attacks and traffic interception through insecure HTTP connections.
How to check redirect chains?
Our tool automatically follows all redirects (301, 302, 307, 308) and shows the complete redirect chain. Long chains slow down page loading and weaken SEO — it is recommended to have no more than 1-2 redirects.
How to set up 24/7 website uptime monitoring?
Sign up free, add a URL on <a href="/en/monitors">/en/monitors</a>, pick an interval (5 min on the free plan, down to 1 min from Navigator) and alert channels (email, Telegram, webhook). The free Scout plan includes 10 monitors forever, no card. On Scout, Explorer and Pioneer checks run from a single location (Moscow); from Navigator up, monitors are checked from multiple locations (13).
What are Core Web Vitals and how to improve them?
Core Web Vitals — 3 Google speed metrics: LCP (main content paint, < 2.5 s — good), CLS (layout shift, < 0.1), INP (click responsiveness, < 200 ms). They affect ranking. Test your site via <a href="/en/speed">/en/speed</a> — the tool returns a 0-100 score and concrete opportunities: lazy-loading, image compression, CSS/JS minification.
Where do alerts go, and which integrations are available?
Monitor down and recovery alerts go to email, Telegram (via our @enterno_io_bot), Slack, PagerDuty and Jira on every plan, including the free one: connect these channels in the Integrations section. Discord and Microsoft Teams get alerts at the webhook URL set on the monitor. HMAC-signed webhooks are on every plan too — use them to connect Zapier, Make, n8n or your own systems. Slack also receives domain expiry, new subdomain and security re-check notifications. Opsgenie and Mattermost are not connected directly — only through a webhook and Zapier, Make or n8n.
200+ HeadersFull set of HTTP response headers
Security HeadersCSP, HSTS, X-Frame-Options and more
Redirects301/302 redirect chains
Custom UASimulate browsers and crawlers
Why teams trust us
150+
headers analysed
HSTS
security check
<2s
response time
Free
no signup needed
How it works
1
Enter URL
2
Get all headers
3
Check security
What are HTTP Headers?
HTTP headers are metadata exchanged between browser and server on every request. They control caching, security, compression, and redirect behavior.
Full Analysis
All response headers categorized: security, cache, content.
Fast Results
Results in seconds from any device without registration.
Redirect Tracing
Visualize redirect chains — each hop with status code and URL.
Check History
Save and compare results — track header changes over time.
Who uses this
DevOps
server header check
Security
CSP, HSTS, X-Frame audit
Developers
cache header debugging
SEO
redirect chain check
Common Mistakes
Missing HSTSWithout HSTS the browser may make the first request over HTTP. Add
Strict-Transport-Security.No Content-Security-PolicyCSP prevents XSS attacks. Even a basic CSP is better than none.
Missing X-Frame-OptionsWithout it, your site can be embedded in an attacker's frame (clickjacking).
Server exposes version
Server: Apache/2.4.51 helps attackers find vulnerabilities. Hide the version.Best Practices
Enable HSTS with preloadThe
preload directive adds the domain to the browser's built-in HSTS list.Configure Cache-ControlUse
immutable for static assets and no-store for sensitive pages.Check after each deployServer updates can reset security headers. Check after every deploy.
Use monitoringSet up an HTTP monitor to get notified when status or headers change.
Get more with a free account
HTTP header check history, API keys and uptime monitoring.
Sign up free