Network Latency Test
Measure network round-trip time from multiple global probe locations. Identify connection latency and network bottlenecks.
About Latency Test
Test network latency and round-trip time from 6 global probe locations. Measure connection latency, TCP handshake time, and network path efficiency.
Key Features
Multi-region latency testing
Time to First Byte (TTFB)
Connection time measurement
DNS lookup time
Historical comparison
Network latency measures the round-trip time (RTT) for data to travel from our probe servers to your target and back—this is fundamentally different from page load speed or bandwidth. High network latency causes delays before any data even begins transferring, affecting everything from API calls to real-time applications.
Our network latency test measures connection-level timing from 6+ global probe locations: TCP handshake time, connection establishment, and round-trip delays. This reveals network path efficiency and geographic performance differences that CDN configuration or server placement can address.
For complete performance analysis, combine network latency testing with TTFB checking to isolate server processing time, and uptime monitoring to ensure availability. Use traceroute to identify which network hops are adding latency.
**Methodology:** TCP connect timing from 6 probe regions measuring DNS lookup, TCP handshake, and connection establishment separately.
Common Errors & How to Fix Them
Click to expand troubleshooting stepsThe server encountered an unexpected condition. This is a generic error when the server crashes or has a configuration problem.
1) For users: wait and retry—often temporary. 2) For site owners: check server error logs (tail -f /var/log/nginx/error.log), verify file permissions, check .htaccess for syntax errors, test PHP/application code locally.
The server acting as a gateway received an invalid response from the upstream server. Common with reverse proxies, load balancers, and CDNs.
1) For users: wait 5-10 minutes and retry. 2) For site owners: check if upstream service is running (systemctl status nginx php-fpm). 3) Verify proxy_pass configuration. 4) Check upstream server logs. 5) Increase proxy timeout values if requests are timing out.
The server is temporarily unable to handle the request due to maintenance or overload. Usually temporary.
1) For users: wait and retry—often means scheduled maintenance. 2) For site owners: check server resources (htop, free -m). 3) Scale up if overloaded. 4) Check if maintenance mode is accidentally enabled. 5) Review rate limiting settings.
The gateway server didn't receive a timely response from the upstream server. The upstream server is too slow or unresponsive.
1) For site owners: increase timeout values (proxy_read_timeout in nginx). 2) Optimize slow backend code/queries. 3) Check database performance. 4) Add caching layers. 5) Test: curl -I -m 30 https://example.com to check response time.
The server didn't respond within the expected time. Could be server overload, network issues, or firewall blocking.
1) Check if server is reachable: ping example.com. 2) Test specific port: nc -vz example.com 443 -w 5. 3) Check from different location (VPN/proxy). 4) For owners: verify firewall allows traffic (ufw status), check server resources, ensure service is running.
The server actively rejected the connection. The service isn't running on the expected port, or a firewall is blocking it.
1) Verify service is running: systemctl status nginx (or apache2, etc.). 2) Check listening ports: netstat -tlnp | grep 443. 3) Verify firewall: ufw status, iptables -L. 4) Check if correct IP/hostname: dig example.com A. 5) Try alternate port if applicable.
Could not establish a secure connection. Certificate may be expired, invalid, or there's a protocol mismatch.
1) Check certificate: openssl s_client -connect example.com:443 -servername example.com. 2) Verify expiry: echo | openssl s_client -connect example.com:443 2>/dev/null | openssl x509 -noout -dates. 3) Check TLS version support. 4) For owners: renew certificate, check intermediate chain, verify SNI configuration.
The domain name couldn't be resolved to an IP address. Domain may not exist, DNS servers may be unreachable, or there's a configuration error.
1) Verify domain exists: whois example.com. 2) Check DNS: dig example.com A @8.8.8.8. 3) Try different DNS server: dig example.com A @1.1.1.1. 4) Flush local DNS cache. 5) For owners: verify NS records at registrar, check DNS provider status.
Frequently Asked Questions
Common questions answeredA website is considered "down" when it cannot be reached or fails to respond to requests. This can mean the server is offline, overloaded, misconfigured, or there's a network issue preventing access. Our tool checks from multiple global locations to determine if the site is down for everyone or just you.
When a website works for others but not you, common causes include: your ISP blocking the site, DNS cache issues on your device, local network problems, or geographic restrictions. Our multi-region checker tests from 6+ locations worldwide to definitively answer whether it's down globally or just for your location.
200 means success—the site is up. 403 means access forbidden (you're blocked). 500 is an internal server error. 502 (Bad Gateway) means the server got an invalid response from an upstream server. 503 (Service Unavailable) means the server is temporarily overloaded or down for maintenance. 504 is a gateway timeout.
A site might be accessible in one region but down in another due to CDN issues, regional server failures, DNS propagation delays, or geographic blocking. Multi-region checking gives you the complete picture. If a site is down in only some regions, it often indicates CDN or load balancer problems rather than a complete outage.
For critical sites, set up automated monitoring that checks every 1-5 minutes. For occasional checks, using this tool when you notice issues is sufficient. ProbeOps offers scheduled monitoring that can alert you via email, Slack, or webhook when your sites go down—before your users notice.
Try these steps: 1) Clear your browser cache and cookies, 2) Flush DNS cache (ipconfig /flushdns on Windows, sudo dscacheutil -flushcache on Mac), 3) Try a different browser or incognito mode, 4) Restart your router, 5) Try a different network (mobile data), 6) Use a VPN to test from another location.
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