1 · Make the receiver audible
Play the receiver audio at a clear, moderate level and allow microphone access. This page listens to audio; it does not tune your radio.
Processed on your device
CW Decoder
Decode CW from a radio played into your microphone. Watch one station, check speed and pitch, then review the text after you stop. It runs locally.
Processed on your deviceNo sign-upReceiver audio · Microphone input
Music excerpt: “Monkeys Spinning Monkeys” by Kevin MacLeod, cropped and mixed with synthesized Morse. incompetech.com · CC BY 4.0
Allow your microphone, then play Morse nearby. Sound stays on this device.
Audio, video and images are processed in your browser. Your files are not uploaded.
2 · Watch one signal
Start capture and follow a single transmission. Nearby stations and room noise can make the rolling interpretation unstable.
3 · Stop and inspect
Stop capture to review the recording. Select one sender’s passage, check its pitch and timing, and replay uncertain call-sign characters.
Receiver setup before decoder adjustments
Use the receiver controls to make the target signal distinct before adjusting the web tool. Keep speaker volume below distortion and reduce other sound sources near the microphone. This browser tool receives the resulting audio; it has no direct RF input, receiver frequency control or built-in rig connection.
Changing senders can change timing
A contact may include senders with different speeds, spacing or audible pitches. Review their passages separately rather than assuming one setting fits the entire exchange. Call signs and numbers need especially careful listening: the decoder maps sound to characters and does not validate a call sign or infer a missing exchange.
Read the characters before interpreting the exchange
-.-. --.- = CQCQ is a short letter group you can use for a controlled practice recording. Decode it, then check a longer practice sequence containing letters and digits. Recognizing CQ does not establish that every character later in a transmission was decoded correctly.
Inspect the pitch and timing of a captured passage →Questions before you start
Does this connect directly to my radio?
No. The default input is microphone audio. The page does not provide CAT control, an SDR receiver or a direct connection to radio hardware.
Can it separate two simultaneous stations?
Overlapping signals remain difficult. Try a passage where one signal is isolated and inspect its pitch; the tool does not promise reliable multi-station separation.
Should I trust the live text for a radio exchange?
Use it as an interpretation to review against the received sound. Live output can change, and the tool does not validate operational details or guarantee the transcript.