WebSocket Tester
Free online WebSocket tester tool, real-time send and receive
About WebSocket Tester
Opens a real WebSocket connection (ws:// or wss://) to a URL you specify, lets you send text messages, and logs every connection lifecycle event and message in a color-coded, timestamped log. The default URL is `wss://echo.websocket.org`, an echo service that replies with whatever you send — useful for quickly verifying that the tool works end to end.
How to Use
1. Type or paste the WebSocket URL into the connection bar (defaults to `wss://echo.websocket.org`). The field is disabled while connected. 2. Click Connect. The status indicator next to the button turns green and a `[INFO] connecting to <url>` log line is recorded. 3. Type a message into the message textarea and click Send. The message is added to the log as a blue `[SEND]` entry and the textarea is cleared. 4. Incoming messages appear as green `[RECV]` entries; lifecycle events (`connected`, `disconnected`, `connection error`) appear as `[INFO]` or red `[ERROR]` entries. 5. Click Disconnect (red) to close the socket. Use Clear in the Log card header to empty the log without disconnecting.
Log Entry Categories and Send Behavior
Every log line carries a timestamp and one of four direction tags, color-coded: - `[INFO]` (muted gray) — connecting, connected, disconnected. - `[SEND]` (blue) — a message you sent via the Send button. - `[RECV]` (green) — an incoming text message; binary frames are logged as the localized "binary data" placeholder rather than their bytes. - `[ERROR]` (red) — the socket fired onerror. Send is gated on the socket being in the OPEN readyState, and the Send button is disabled unless both connected and the message field is non-empty. Each sent message is appended to the log and the field is cleared immediately, so re-sending requires retyping.
▶Can I send binary data or receive binary frames?
▶Does connecting send data to a server?
▶Why is the Send button disabled even though I typed a message?
▶Why did nothing happen after I clicked Connect?
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