Zernio
Zernio
API Reference

Voice & Calling

Calls

List phone callsGETPlace an outbound phone callPOSTGet a phone callGETHang up a live callPOSTBlind-transfer a live callPOSTGet a call recordingGETEstimate call costGET

Browser Softphone

Mint a browser softphone sessionPOSTDial from the browser softphonePOST

Number Setup

Enable phone calling on a numberPOSTDisable phone calling on a numberDELETEAttach a number to a SIP trunkPOSTDetach a number from its SIP trunkDELETE

SIP Trunks

List SIP trunksGETCreate a SIP trunkPOSTGet a SIP trunkGETDelete a SIP trunkDELETERotate a SIP trunk's passwordPOST
Dashboard
llms.txtOpenAPI
OverviewPlatformsAPI ReferenceResources
Voice & Calling

Get a call recording

Resolves a fresh, playable MP3 URL for the call's recording (provider-signed URLs expire ~10 minutes after signing, so this endpoint re-signs on demand). Default responds 302 Found redirecting to the fresh URL; pass as=json to receive { url } instead.

GET
/v1/voice/calls/{id}/recording

Authorization

bearerAuth
AuthorizationBearer <token>

API key authentication: send your Zernio API key in the Authorization header, prefixed with Bearer.

In: header

Path Parameters

id*string

Query Parameters

as?"json"

json returns { url } instead of a 302 redirect.

Value in

  • "json"

Response Body

application/json

application/json

import Zernio from '@zernio/node';const zernio = new Zernio({ apiKey: process.env.ZERNIO_API_KEY });const { data } = await zernio.voice.getVoiceCallRecording({  path: {    id: 'abc123',  },});console.log(data);
{  "url": "string"}
Was this page helpful?

Blind-transfer a live call

Moves the call's current leg to a new destination (a phone number or a SIP endpoint). This is a BLIND transfer: control of the leg is handed off and the call ends normally when the transferred leg hangs up. The caller ID presented on the transfer leg is always your own number.

Estimate call cost

Pre-call cost estimate for a PSTN call: the carrier leg plus optional recording and transcription add-ons. Same billing formula as the post-call invoice, so the quote and the final charge can't disagree. The per-minute figure is deliberately conservative (the real cost comes from the settled carrier record after the call), so estimates trend slightly over the actual invoice. Parity endpoint of `GET /v1/whatsapp/calls/estimate`, minus the Meta line (PSTN calls have no separate Meta bill, so `totalCostUSD` equals `billableCostUSD`).