Make and receive calls from your own WhatsApp
A complementary voice channel: call your customers, answer incoming calls and run mass-calling campaigns — all from your own WhatsApp number, with stereo recording, metrics and flat per-number pricing.
João Silva
+55 11 99999-1234
11 9 9999-1234
Built on a production voice stack — clean audio, stereo recording and low latency.
New voice engine · more stable and lightweight
Everything you need
Dialer, recording, metrics and integrations — in one platform.
Receive and answer calls
Answer calls that come in to your WhatsApp number — right from the browser dialer. Available now.
Mass calling
Upload a list of numbers: Hasos dials them one by one and, on the first pickup, you talk in the dialer — the rest are ended.
Stereo recording
Every call recorded in stereo — you on the left, contact on the right. Listen and download from the dashboard anytime.
Embeddable dialer
One iframe and your users make and receive WhatsApp calls right inside your app, with no voice infrastructure to run.
SIP accessNew
Register your softphone (Zoiper, Linphone) or PBX (Asterisk, 3CX) with host, username and password and use WhatsApp over SIP — no new number. Pro plan.
Signed webhooks
Real-time call events (ringing, answered, ended, record), with HMAC signatures and a delivery log.
CRM integrationBeta
Connect RD Station, Pipedrive or HubSpot and every call becomes an activity on the contact — with status, duration and recording link.
Metrics
Answer rate, average duration and volume — ready for your dashboard.
Durable sessions
The WhatsApp connection survives restarts and deploys. No need to re-pair.
Multi-number
Multiple numbers on the same account. 1 concurrent call per number — N numbers = N calls at the same time.
REST API
Provision numbers, issue tokens and manage everything via /v1 — authenticated with an API key.
Hours & VoicemailBeta
Set your business hours and record a greeting: after hours, callers hear your message and leave a voicemail (it lands in Recordings).
AI attendant (ElevenLabs)
Connect your ElevenLabs agent (BYOK) and the AI answers incoming calls by voice.
For developers
A complete /v1 REST API, an embeddable dialer via iframe and signed webhooks. Integrate in minutes, with no voice servers to maintain.
- 1Create your API key in the dashboard
- 2Connect a WhatsApp number via QR Code or pairing code
- 3Drop the dialer iframe into your app — or use the API directly
Create an instance via API
curl -X POST https://api.hasos.com.br/v1/instances \
-H "x-api-key: hs_live_your_key" \
-H "Content-Type: application/json" \
-d '{"phone":"5511999999999"}'Embed the dialer
<iframe src="https://app.hasos.com.br/discador?token=YOUR_TOKEN" allow="microphone" style="width:420px;height:640px;border:0;border-radius:8px" ></iframe>
Simple pricing
Start for free. Upgrade as you grow.
Priced per WhatsApp number. Each number handles 1 call at a time (a WhatsApp limit) — to talk in parallel, connect more numbers (N numbers = N calls at the same time).
1 number · from the 2nd, $29 per number (2 → $68, 3 → $97)
- Unlimited calls
- 1 concurrent call per number (N numbers = N at once)
- Mass calling
- Recording and metrics
- Webhooks and API
- SIP access (softphone/PBX)
- Unlimited numbers
- 1 call per number (N numbers = N concurrent)
- SLA + support
Add it to Pro or Enterprise. Every recorded call gets an AI transcript and summary, delivered to your webhook too — and the AI voice attendant (ElevenLabs) is unlocked.
- Automatic transcription of recordings
- Summary with next steps
- Transcript in the webhook (TRANSCRIPT event)
- AI voice attendant (ElevenLabs)
Frequently asked questions
- What is Hasos?
- A platform to make and receive calls using your own WhatsApp number: a browser dialer with stereo recording, metrics, mass calling and answering of incoming calls — plus a complete API (embeddable dialer, signed webhooks) for teams that want to integrate. Includes an AI voice attendant (ElevenLabs, BYOK).
- How does billing work?
- The Pro plan is priced per WhatsApp number: 1 number is $39/mo and, from the 2nd, $29 per number (2 → $68, 3 → $97). Unlimited calls. There is a Free plan to try it out.
- Do I need a dedicated phone number?
- No. You connect an existing WhatsApp number via QR Code or pairing code. The session is durable and survives restarts.
- Can I record calls?
- Yes. Stereo recording is available in the dashboard to listen to and download, stored securely.
- How do I receive call events?
- Via signed webhooks (HMAC SHA-256): you validate the x-webhook-signature and receive real-time call events on your server.
- How long does it take to integrate?
- Minutes: create an API key, connect a number and embed the dialer via iframe — or use the REST API directly.
From the blog
Guides and comparisons on the WhatsApp calls API.
SIP para WhatsApp: use seu softphone ou PABX com o número conectado
Host, usuário e senha: registre seu softphone ou PABX e use o WhatsApp por SIP — sem número novo e com a mesma gravação.
Read articleVoIP no WhatsApp: transforme a voz do WhatsApp em VoIP (SIP + API)
SIP, discador e API sobre o seu número: a voz do WhatsApp virando VoIP na sua operação, com preço fixo por número.
Read articleComo conectar seu PABX (Asterisk, Issabel, 3CX) ao WhatsApp por SIP
Trunk ou ramal SIP no Asterisk/Issabel/3CX apontando para o seu número — com exemplo de pjsip.conf.
Read articleReady to add voice to your product?
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