Phone numbers
Phone number API
for AI voice agents
Vobiz gives your AI voice agent a local, mobile or toll-free DID in 130+ countries. Live in seconds, assigned to your agent in one call, and kept off spam lists with spam label monitoring and CNAM registration. Works with Vapi, Retell AI, LiveKit, ElevenLabs, Pipecat and OpenAI Realtime.
Talk to us
LIVE130+Countries
DIDs
190+Countries
outbound calling
10min
to first call
30%
fewer spam flags on managed numbers
How it works
Buy a phone number by API and route it
to your agent in three calls
No ticket, no provisioning window. Every step works from the console or the REST API.
API key123Live call- +1 415 555 0100
- +1 415 555 0101
- +1 415 555 0102
1# 1. Find US numbers containing 4152curl "https://api.vobiz.ai/api/v1/Account/$AUTH_ID/inventory/numbers?country=US&search=415&per_page=25" \3-H "X-Auth-ID: $AUTH_ID" -H "X-Auth-Token: $AUTH_TOKEN"4 5# 2. Buy one6curl -X POST "https://api.vobiz.ai/api/v1/Account/$AUTH_ID/numbers/purchase-from-inventory" \7-H "X-Auth-ID: $AUTH_ID" -H "X-Auth-Token: $AUTH_TOKEN" \8-H "Content-Type: application/json" -d '{"e164":"+14155550100","currency":"USD"}'9 10# 3. Route inbound calls to your trunk (+ is encoded as %2B)11curl -X POST "https://api.vobiz.ai/api/v1/Account/$AUTH_ID/numbers/%2B14155550100/assign" \12-H "X-Auth-ID: $AUTH_ID" -H "X-Auth-Token: $AUTH_TOKEN" \13-H "Content-Type: application/json" -d '{"trunk_group_id":"<your-trunk-id>"}'
Number types
Local, toll-free and mobile DIDs
for every call your agent makes
Every Vobiz number is a DID: a real phone number that routes straight to your trunk or application.
Local(US area codes)
Toll-free
Mobile
National and special series(outside the US)
YesYesYesYesYesYesYes
Per country rulesPer countryNumber health
Keep your numbers from
being flagged "Spam Likely"
A call from a number your customer doesn't recognize, or one their phone labels spam, is a call your agent never gets to make.
Vobiz runs number health as an operated service. Spam labels on managed numbers are monitored, and we handle the CNAM registration that carriers look for.
Local presence
choose a local number in every market you operate in so customers see a number that feels familiar.
Spam label monitoring
managed numbers are watched for carrier spam labels, with guidance on safe daily volumes and rotation before a number degrades.
Know why a call failed
per-call hangup attribution separates a carrier rejection from an agent that lost the caller.
30%
reduction in spam flag rate on managed numbers
Coverage and requirements
Local, toll-free and mobile numbers in 130+ countries with registration support
Your AI agent's reach is only as wide as the numbers behind it.
Self-serve, instant provisioning of DIDs across local, toll-free and special series numbers in the US, APAC including India, and EMEA. Where a country requires proof of address or business identity, Vobiz collects it once and manages the filing for you. Outbound calls reach 190+ countries.
AmericasAssign anywhere
One number, any part of your stack,
reassigned in one call
Assign a number to a SIP trunk, a Voice API application or a sub-account, and move it later without releasing or re-buying it.
Phone number+1 415 555 0100
To a SIP trunkinbound calls on the number go to your trunk, and on to Vapi, Retell AI, LiveKit or your PBX.POST /Account/{auth_id}/numbers/{number}/assignwithtrunk_group_id
To a Voice API applicationVobiz requests your answer URL when the number rings, and you return VobizXML or open a stream.applications/attach-number
To a sub-accounthand a number to one of your customers' tenants, billed to your parent account.POST /account/{auth_id}/numbers/{number}/assign-subaccount
Releasereturn a number you no longer need and stop its billing.DELETE /Account/{auth_id}/numbers/{number}
Numbers at platform scale
Manage thousands of numbers
across your customers by API
List every number across your account and sub-accounts, with its status, assignment, monthly fee and next billing date in one response. Tag numbers by customer, campaign or region, and give each tenant its own number pool, credentials and billing.
Sub-accounts and the partner API
Customer C+1 415 555 0100
Integrations
A phone number for Vapi,
Retell AI, ElevenLabs and
the agent you already run
Buy the number on Vobiz, then connect it to your platform the way that platform takes calls.
·
Assign to a SIP trunk, import into the platform/integrations/vapi-dashboard/
/integrations/retellai-dashboard/
Agents
Realtime
·
Dograh·custom pipelines
Assign to a Voice API application that streams over WebSocketPipecat guide
Audio streaming docs
Get started
Give your agent a number
in the next 10 minutes
Search, buy, assign, call.
No ticket, no sales call, no commitment.
FAQ
Phone number questions
- An API that lets your software search, buy, assign and release phone numbers itself, rather than through a ticket or a portal. Vobiz numbers are bought and routed with the same REST API your agent already uses.
- Search inventory by country and digits, buy the number with one request, then assign it to a SIP trunk for Vapi, Retell AI or LiveKit, or to a Voice API application that streams to your own pipeline.
- A DID is a real phone number that routes straight to your trunk or application. Every Vobiz number — local, toll-free, mobile or national — is a DID.
- Local, toll-free and mobile numbers are available in 130+ countries across the US, APAC including India, and EMEA. Outbound calls reach 190+ countries.
- Yes. Where a country requires proof of address or business identity, Vobiz collects it once and manages the filing for you. The requirements page lists what each country asks for.
- Managed numbers are monitored for carrier spam labels, carry CNAM registration and come with guidance on safe daily volumes and rotation. That cuts the spam flag rate on managed numbers by around 30%.
- Yes. A number can be reassigned to another SIP trunk, Voice API application or sub-account in one call, without releasing or re-buying it.
- Yes. Sub-accounts give each tenant its own number pool, credentials and billing, and you can list every number across them in one response.
The Infrastructure Platform for Voice AI Builders and Integrators
Your brand. Your pricing. Vobiz under the hood.
Run your voice AI business through a single API. Provision customer accounts, control billing, and manage DID inventory, call records, and financial reconciliation in real-time. You own the customer relationship. We power the infrastructure behind it.
Related
Resources