# Vonage (Nexmo) API

**Provider:** Vonage
**Category:** communication
**Base URL:** `https://rest.nexmo.com`
**Auth:** basic — `Authorization: Basic base64(api_key:api_secret)`
**Rate Limit:** 30 messages/sec (SMS)
**Free Tier:** Yes — [object Object]
**Pricing:** from $0.01/mo (pay-as-you-go)
**Docs:** https://developer.vonage.com/en/api

## Description

Vonage (formerly Nexmo) provides a suite of communication APIs for building messaging, voice, and video features. Send SMS globally, make and receive programmatic voice calls with TTS and IVR flows, verify phone numbers via OTP, implement WebRTC video sessions, and manage virtual phone numbers. The Vonage Application API ties everything together under a single project.

## Endpoints

| Method | Endpoint | Description |
|--------|----------|-------------|
| POST | `https://rest.nexmo.com/sms/json` | Send an SMS message to any phone number |
| POST | `https://rest.nexmo.com/verify/json` | Send OTP verification code via SMS or voice |
| POST | `https://rest.nexmo.com/verify/check/json` | Verify the OTP code entered by the user |
| POST | `https://rest.nexmo.com/v1/calls` | Initiate an outbound voice call with NCCO flow |
| GET | `https://rest.nexmo.com/v1/account/numbers` | List virtual phone numbers in your account |
| GET | `https://rest.nexmo.com/ni/basic/json` | Number Insight — validate and look up a phone number |

## Authentication

Use your API Key and API Secret as Basic Auth credentials, or generate JWTs for newer API endpoints.

```
Authorization: Basic base64(api_key:api_secret)
```

## Sample Request

```bash
curl "https://rest.nexmo.com/sms/json" \
  -H "Content-Type: application/json" \
  -d '{"api_key":"$VONAGE_API_KEY","api_secret":"$VONAGE_API_SECRET","to":"14155552671","from":"Vonage APIs","text":"Hello from Vonage!"}'
```

## Sample Response

```json
{
  "message-count": "1",
  "messages": [{
    "to": "14155552671",
    "message-id": "0C000000DA7CFAE5",
    "status": "0",
    "remaining-balance": "3.14159",
    "message-price": "0.00570000",
    "network": "310090"
  }]
}
```

## Pricing Details

SMS: from $0.0079/message. Voice calls: from $0.0043/min. Number Insight: $0.005/lookup. Verify API: $0.055/successful verification. Phone number rental: $1–3/month.

---

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