# Twilio API

**Provider:** Twilio
**Category:** communication
**Base URL:** `https://api.twilio.com/2010-04-01`
**Auth:** basic — `Authorization: Basic base64(AccountSID:AuthToken)`
**Rate Limit:** 1 request/s per phone number
**Free Tier:** Yes — [object Object]
**Pricing:** Pay per use (pay-as-you-go)
**Docs:** https://www.twilio.com/docs/usage/api

## Description

Twilio's API platform powers communications for millions of developers. Send and receive SMS/MMS, make and receive voice calls, build IVR systems, send WhatsApp messages, verify phone numbers and users with OTP, and send transactional email via SendGrid (Twilio subsidiary).

## Endpoints

| Method | Endpoint | Description |
|--------|----------|-------------|
| POST | `https://api.twilio.com/2010-04-01/Accounts/{SID}/Messages.json` | Send an SMS or MMS message |
| GET | `https://api.twilio.com/2010-04-01/Accounts/{SID}/Messages.json` | List messages |
| POST | `https://api.twilio.com/2010-04-01/Accounts/{SID}/Calls.json` | Initiate a voice call |
| POST | `https://api.twilio.com/2010-04-01/Accounts/{SID}/IncomingPhoneNumbers.json` | Buy a phone number |

## Authentication

HTTP Basic Auth using your Account SID as username and Auth Token as password.

```
Authorization: Basic base64(AccountSID:AuthToken)
```

## Sample Request

```bash
curl -X POST https://api.twilio.com/2010-04-01/Accounts/$TWILIO_ACCOUNT_SID/Messages.json \
  -u "$TWILIO_ACCOUNT_SID:$TWILIO_AUTH_TOKEN" \
  --data-urlencode "To=+15005550006" \
  --data-urlencode "From=+15017122661" \
  --data-urlencode "Body=Hello from Twilio!"
```

## Sample Response

```json
{
  "sid": "SM87105da94bff44b999e4e6eb90d8eb6a",
  "status": "queued",
  "to": "+15005550006",
  "from": "+15017122661",
  "body": "Hello from Twilio!",
  "price": "-0.00750",
  "date_created": "Thu, 18 Jan 2024 12:00:00 +0000"
}
```

## Pricing Details

SMS: $0.0079/message. Voice: $0.0085/min. WhatsApp: $0.005/message. Free trial includes $15 credit. Volume discounts available.

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*Source: [API Map](https://apimap.dev/apis/twilio/) — CC BY 4.0*