Test any public API endpoint in real-time. Measure response latency in milliseconds, inspect HTTP status codes, TLS encryption, and response headers.
Unlike browser fetch() which blocks requests when target endpoints lack Access-Control-Allow-Origin, Uptara executes real HTTP/S probes directly from our backend edge runners. You can inspect public APIs, internal microservices, and webhook receivers with zero CORS blocking.
200 OK
Endpoint Operational42 ms
⚡ Fast (<200ms)HTTP/2
Negotiated Wire74d left
Let's Encrypt Authority E60 hops
Direct TargetUS-East (Global Edge)
Probe OriginEvery probe executes a real HTTP transaction from our edge infrastructure, capturing deep telemetry across six vital dimensions:
Evaluates standard HTTP response codes across 2xx (nominal success), 3xx (redirections), 4xx (client errors), and 5xx (upstream server failures or crashes).
Calculates total execution duration in milliseconds, encompassing DNS resolution, TCP handshake, TLS cryptographic negotiation, and Time to First Byte (TTFB).
Detects whether the upstream server negotiated HTTP/2 (multiplexed streams over a single connection) or standard HTTP/1.1 with persistent keep-alive.
Validates HTTPS certificate chains, identifies the Certificate Authority (CA) issuer, and tracks remaining validity days before certificate expiration.
Follows HTTP 301, 302, 307, and 308 redirect chains, counting hop traversal to verify canonical destination resolution and detect potential infinite loops.
Inspects all returned HTTP response headers (content-type, cache-control, server) and validates response payload snippets.
This tool dispatches a live HTTP/HTTPS probe directly from Uptara edge nodes to your target URL. It measures exact round-trip latency, negotiates the transport protocol (HTTP/2 or HTTP/1.1), verifies the TLS/SSL handshake, tracks redirects, and inspects HTTP response headers.
Standard browser-based fetch tools run inside your web browser and are restricted by Cross-Origin Resource Sharing (CORS) security policies if the API does not set Access-Control-Allow-Origin headers. Uptara executes checks server-to-server from our global edge infrastructure, meaning you can test any public API, internal service, or webhook receiver without CORS interference.
Latency measures total network round-trip time in milliseconds, encompassing DNS resolution, TCP connection establishment, TLS/SSL cryptographic handshake, and Time to First Byte (TTFB) from the server response.
You can create a free Uptara account to run scheduled probes 24/7 (every 3 minutes on the Free tier with 10 free monitors, down to 30 seconds on Pro plans) across multiple global regions with instant alerts on WhatsApp, Slack, PagerDuty, and email.
Yes. In your Uptara dashboard, you can configure synthetic monitors with custom HTTP methods (GET, POST, PUT, DELETE, PATCH), custom request headers (Authorization, Bearer tokens, API keys), JSON request payloads, and assertion checks on status codes or response bodies.
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