Voice resource library
A better call starts with a useful answer.
Choose a calling path, prepare the connection and understand the result. Find practical guides, technical references and clear explanations, connected to the Voice capability you want to build.
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Read more customer storiesStart with your customer journey
SIP trunkingConnect your PBX, softphone or SIP application to the telephone network.Call sequencesTurn prompts, keypad choices and named branches into a versioned workflow.AI VoiceBring a conversational runtime to the phone, with your context, tools and handoff.Inbound routingConnect each number to your phone system, forwarding target or call sequence.Browser callingPlace an outbound call from your workspace with a browser phone and your SIP trunk.Recordings and transcriptsReview captured audio and transcripts alongside the call that produced them.Voice analyticsUnderstand outcomes, duration and rated costs, then inspect the individual call.Outbound callingConnect callbacks and service conversations, then reconcile the final call outcome.Voice numbersPrepare inbound numbers, caller identity and a supported number migration.Contact center connectionsKeep your agent workflows and connect the telephone network through SIP.WhatsApp customer conversationsContinue customer conversations on WhatsApp.
Configure and operate Voice
Call logBrowse, filter, and export every call your workspace placed or received, and read why a call was refused: statuses, timings, billable time, and cost.Call sequencesDesign and publish Bird Voice sequences for greetings, keypad menus and outbound notifications, with controlled testing and consistent call behavior.Caller IDsRegister the numbers your workspace presents on outbound calls and prove you own them with a verification call, on the Numbers page in the dashboard.Voice destinationsChoose the countries your workspace calls by enabling them on the Destinations page, and read what the availability and high risk labels mean on that list.Voice eventsThe three voice call webhook events, what each one means in the life of a call, the fields they carry, and how to consume them without double counting.Place your first callPlace a browser call through a SIP trunk, confirm two-way audio, and inspect the resulting call record in the dashboard or Voice API.Voice overviewWhat Bird Voice is, how a call travels between your phone system and the telephone network over a SIP trunk, and where your calls show up.PhonePlace calls from the Bird dashboard over your own SIP trunk: what a browser call needs, the controls during a call, and where the calls show up.Placing callsWhat has to be true before your first outbound call, what Bird expects on the SIP INVITE, how the Digest handshake works, and how a call is priced.Receiving callsPoint a number you hold at one of your SIP trunks or forward it to a verified number, and read what a number did with an incoming call.Recordings and transcriptsReview captured Voice audio and transcripts in context, follow artifact processing and connect each recording to the call and session that produced it.SIP client setupPoint a softphone or a PBX at a Bird SIP trunk, with the settings every client needs and worked configurations for Asterisk, FreePBX, Zoiper, and baresip.SIP trunksCreate a SIP trunk, turn on each direction, read its connection details, and control which addresses, API keys, and session credentials may send calls to it.Voice troubleshootingDiagnose a Bird Voice call from its symptom: missing from the call log, rejected with or without a reason, an incoming call nobody answers, or one-way audio.Connect an AI voice applicationPrepare the SIP connection, business actions and human handoff.
Voice explained
WebRTC vs SIP, which do I use for a browser or an AI agent?They are not alternatives. WebRTC specifies the media and leaves signaling out on purpose, and SIP is signaling. A browser call usually runs both.What do SIP response codes mean, and why did I get a 503?The codes are HTTP-shaped and mostly read that way. The exception matters: a 503 from Bird is a refusal it will not explain on the wire, not an overload.What is a call detail record (CDR)?One record per call leg, carrying the outcome, the timings and the cost. Not every call produces one, and the cost arrives after the call does.What is a SIP trunk, and do I need one?A trunk connects your side to Bird's network, and every call crosses one. What differs is whether a phone system or a lighter SIP client sits behind it.What is a voice AI agent, and how does it connect to the phone network?Understand the conversational runtime, telephone connection and confirmed business outcome.What is a voice API?Understand call control, SIP connectivity and the records behind a conversation.What is SIP?SIP arranges calls and then steps out of the way. The audio travels on a separate path, which is why a call that connects with no sound is a normal failure.What is STIR/SHAKEN, and what are attestation levels A, B and C?Attestation is a claim the signing provider makes about what it checked, not a score for your call. A, B and C say how much of you it could vouch for.What is toll fraud, and how does Bird limit it?An attacker dials premium numbers through your phone system. Bird refuses those number types, a country list bounds the rest, and ceilings cap the spend.What is VoIP?VoIP carries calls as IP packets. The consequential category is interconnected VoIP, which turns on access to the public switched telephone network.Why is my call labeled Spam Likely or Scam Likely?The label is applied by the carrier that delivers the call, not the one that carried it. Blocking and labeling are different, and only one has a route back.
Plan a Voice migration
Migrate from TwilioMap TwiML, call control, numbers and conversation behavior to the replacement workflow.Migrate from TelnyxPlan SIP, call control and managed-assistant responsibilities before moving traffic.Migrate from VonageMap NCCO instructions, webhooks and number routing to the Bird call lifecycle.Migrate from VapiDecide whether to change the telephone connection, the assistant runtime or both.Migrate from BlandInventory Pathways, tool actions, SIP routing and the evidence each call must retain.Migrate from BandwidthMap SIP realms, numbers and the application behind your calls.Migrate from PlivoMap Zentrunk connectivity and any call-control dependencies before a cutover.
Make your next decision
Voice platformReturn to the complete calling platform.Voice FAQsBrowse practical questions by capability.Getting startedPrepare and verify a controlled first call.Voice pricingReview destination rates and the components of your call.Voice comparisonsCompare the calling model and migration path across providers.
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Put the guide to work.
Follow the setup guide that matches your calling path. Bring the workflow and the point where you need help to our Voice team.