Is the online website uptime checker free?

Yes, completely free with no registration required. All checks are initiated from your browser without going through any intermediate server.

Are the results accurate?

Results reflect connectivity from your network to the target website. Since requests originate from your browser, results are affected by your local network. CORS restrictions may limit full response details, but basic connectivity checks remain valid.

HTTP status code, response time measurement, HTTPS/SSL availability, and redirect tracking. Supports batch checking multiple URLs with one-click result copy.

Why do some sites show as unreachable?

Possible reasons: 1) The site is actually down; 2) CORS policy blocks cross-origin requests; 3) The site blocks direct browser access; 4) Your network can't reach it. Cross-verify with other tools.

Can it auto-monitor on a schedule?

The current version supports manual trigger checks. You can click the check button anytime while the page is open. Scheduled auto-check is planned for a future version.

Uptime Checker

Batch check website HTTP status, response time, and SSL availability

Zero Dependencies · Works Offline

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Home › Network Tools › Uptime Checker

🌐 Website Status Check

🔒 All checks originate from your browser directly, no intermediate servers

What Can the Uptime Checker Do?

The online website uptime checker is a free pure frontend tool that helps you quickly check the online status of multiple websites. It sends HTTP requests directly from your browser to get status codes, response times, and SSL information — no software installation needed.

Core Features

Batch Check: Enter multiple URLs at once, check each sequentially
HTTP Status Code: Get 200/301/403/404/500 status codes
Response Time: Measure request-to-response latency
SSL Check: Verify if HTTPS is enabled
Export Results: One-click copy results to clipboard

How to Use

Enter URLs to check in the input box, one per line
Click "Start Check"
Wait for results showing status code, response time, and SSL status
Click "Copy Results" to export

Use Cases

Ops Patrol

Operations engineers can quickly batch-check multiple services' online status and catch anomalies early. Lighter and faster than logging into monitoring platforms.

Post-Deploy Verification

After deploying a new version, quickly verify all service URLs respond normally to confirm successful deployment.

Competitor Monitoring

Track competitor website availability to understand their service stability.

Extended Knowledge

Website uptime is a core service quality metric, typically expressed as a percentage (e.g., 99.9%). HTTP status codes indicate server response: 2xx = success, 3xx = redirect, 4xx = client error, 5xx = server error. SSL/TLS certificates provide encrypted connections, the foundation of modern web security. This tool uses the browser's fetch API, subject to CORS policy — some cross-origin requests may not return full response details.

FAQ

Why do some sites fail to check?

CORS policy may block cross-origin requests, or the target site may block direct browser access. This doesn't necessarily mean the site is down — cross-verify with other tools.

Is response time accurate?

Response time reflects latency from your browser to the target, affected by your local network. Results may vary across different network environments.

How many URLs can I check?

No hard limit, but we recommend no more than 20 URLs per batch to avoid browser concurrency issues affecting accuracy.