Twilio - Api
Twilio - Api
Twilio's core API for voice calls, SMS, Verify, and other programmable communications, billed per usage.
Global phone-number and SMS coverage
Per-message and per-minute pricing adds up at scale
Sign up at twilio.com, copy the Account SID and Auth Token from the Console, and authenticate with HTTP Basic (SID:token). Trial accounts get a small credit; buy a phone number before sending real SMS. For production prefer API Keys over the master Auth Token.
Uptime · 30-day window
About this API
Twilio turns telecom networks into HTTP APIs, letting developers place calls, send messages, and run identity flows with familiar request/response shapes. At its core is TwiML — an XML markup language that describes what happens when a call connects: answer, transfer, record, play audio, gather digits.
The product surface is broad but cohesive: Programmable Voice handles calls, Programmable Messaging handles SMS/MMS, Verify runs OTP flows, Conversations orchestrates multichannel threads, and Studio offers a drag-and-drop builder for non-engineers. All share the same auth and phone-number pool, making cross-product workflows straightforward.
Pricing is per-usage (per SMS, per minute, per OTP). There is no monthly fee but costs scale linearly with traffic. Several countries require registered sender identities (A2P 10DLC, Toll-Free, Sender ID); skipping that step leads to filtering or blocks. Brand-new accounts also face stricter anti-fraud throttles on the first sends.
What you can build
- 1Send programmatic SMS and MMS
- 2Build inbound/outbound voice and IVR flows
- 3Add OTP verification with Verify
- 4Record calls and capture delivery receipts
- 5Orchestrate conferences, transfers, and voicemail with TwiML
Strengths & limitations
Strengths
- Global phone-number and SMS coverage
- Interactive, high-quality documentation
- TwiML makes call flows feel like writing markup
- Mature SDKs and a polished CLI
Limitations
- Per-message and per-minute pricing adds up at scale
- Some countries require sender ID registration or 10DLC compliance
- New accounts face stricter anti-fraud throttles on first send
Example request
curl https://support.twilio.com/<endpoint> \
-u "$USERNAME:$PASSWORD"Getting started
Sign up at twilio.com, copy the Account SID and Auth Token from the Console, and authenticate with HTTP Basic (SID:token). Trial accounts get a small credit; buy a phone number before sending real SMS. For production prefer API Keys over the master Auth Token.
FAQ
How much does one SMS cost?+
Priced per destination country — US local is around $0.0083/message, international varies widely. See twilio.com/sms/pricing.
Do I need to buy a phone number?+
Yes, sending SMS or making calls requires at least one Twilio number or registered sender. US local numbers are about $1.15/month.
Can I call the API directly from a browser?+
Credentials should not be exposed client-side; proxy through your server. Browser-side use (Video, Voice JS SDK) is authorized via short-lived access tokens.
Why use Verify instead of rolling my own OTP?+
Verify handles retries, fraud detection, multi-channel fallback, and global routing, and lifts compliance burden off your team.
Technical details
- Auth type
- basic
- Pricing
- paid
- Protocols
- REST
- SDKs
- python, javascript, typescript, java, ruby, go, php, csharp
- Response time
- 394 ms
- Last health check
- 5/12/2026, 7:38:31 AM
Endpoints
Parsed from the OpenAPI spec. Showing 12 of 199 non-deprecated endpoints.
/2010-04-01/Accounts.json/2010-04-01/Accounts.json/2010-04-01/Accounts/{AccountSid}/Addresses.json/2010-04-01/Accounts/{AccountSid}/Addresses.json/2010-04-01/Accounts/{AccountSid}/Addresses/{AddressSid}/DependentPhoneNumbers.json/2010-04-01/Accounts/{AccountSid}/Addresses/{Sid}.json/2010-04-01/Accounts/{AccountSid}/Addresses/{Sid}.json/2010-04-01/Accounts/{AccountSid}/Addresses/{Sid}.json/2010-04-01/Accounts/{AccountSid}/Applications.json/2010-04-01/Accounts/{AccountSid}/Applications.json/2010-04-01/Accounts/{AccountSid}/Applications/{Sid}.json/2010-04-01/Accounts/{AccountSid}/Applications/{Sid}.json187 more endpoints not shown. See the OpenAPI spec for the full list.
More from Twilio
Manage Twilio account credentials and hierarchy — create subaccounts, rotate auth tokens, and look up account metadata.
Twilio Autopilot is a sunset conversational-AI platform formerly used for IVR bots and NLU tasks (now superseded; migrate to Voice Intelligence or third-party LLMs).
Bulk-export Twilio usage history (Messages, Calls) as compressed daily JSON files — for audit, billing reconciliation, or data-warehouse ingestion.
Twilio Chat v1 is a sunset real-time chat SDK backend (superseded by Conversations). Existing projects still work; new projects should use Conversations API.
Twilio Content API centrally manages messaging templates across channels (WhatsApp/SMS/Messenger), including WhatsApp template approval flow and dynamic variable binding.
Twilio Conversations unifies multi-channel (SMS/MMS/WhatsApp/Chat/Email) messaging into a single "conversation" primitive with multi-participant, persistence, and read receipts.
Twilio Events streams Twilio platform events (message delivery, call state changes, quota alerts) via a unified webhook bus — replacing scattered per-endpoint webhook configs.
Twilio Flex is a programmable contact-center platform for call centers — agent desktop, IVR/ACD routing, and deep integration with Twilio's full communications stack.
Alternatives to consider
Different providers solving similar problems. Picked by category, auth, pricing, and tag overlap.