Answering-machine detection, as an API.
Send the first seconds of a call. A person goes to your agent as soon as they finish their hello. A machine is let go at 2 seconds, never later than 5: no shorter calls (they hurt your traffic and are billed as 6 s anyway), and no slower than the AMD you have now.
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No card for the test key. 100,000 free detections when you go live.
curl https://api.byebeep.com/v1/detect \
-H "Authorization: Bearer bb_test_YOUR_KEY" \
-F audio=@call.wav{
"verdict": {
"class": "machine",
"subtype": "voicemail",
"decided_ms": 2000,
"sure_ms": 320,
"decided_by": "fingerprint"
}
}Measured on 948 recorded calls the engine was not trained on (518 people, 430 machines), November 2026, each labelled by the dialer's existing AMD unless a person reviewed the recording. Times count from the moment the call is answered. Most machines are recognised within a second and held to 2 s; a call screener is held to 5 s in case a person picks up.
Stream, don't upload
Open a WebSocket when the call is answered and send the audio as it comes. The verdict arrives during the call, not after it. Recordings work too, with one POST.
Careful with people
Hanging up on a person costs a sale and counts against your abandonment rate, so ByeBeep only says "machine" when it is sure. When it isn't, it says "unsure", and you treat that as a person.
Knows the greetings
Carrier voicemail prompts and call screeners repeat across many numbers. ByeBeep recognises the ones it has heard, gives a call screener until the end of the window in case a person picks up, and waits out network announcements like "your call has been forwarded".
Works with what you dial from
Try it in the browser
The portal's playground streams a sample voicemail, your microphone or a recording to the live API and marks the verdict on the waveform.
See every call
A log of every detection for 30 days: verdict, when and how it was decided, by key and call ID.
No audio kept
Call audio is processed in memory and not stored. We keep a usage record (time, key, verdict, timings) for billing and support.
Pricing
Per detection, billed monthly. Calls with no audio are free.
| Monthly volume | Core per 1,000 | Plus per 1,000 |
|---|---|---|
| First 250,000 | $0.30 | $1.50 |
| 250,000 to 1 million | $0.12 | $1.50 |
| 1 million to 10 million | $0.06 | $1.10 |
| Over 10 million | $0.06 | $0.75 |
Core: verdict, kind of machine, timings, webhooks. Plus adds the voicemail beep's timing and late correction. 100,000 detections free once, and your first 30 days live are a free trial beside your current AMD. A month with any charge is at least $29.