Quick Start

Get up and running with the SendAPI platform in under 5 minutes.

By the end of this guide, you will have created a SendAPI account, verified your email, obtained an API key, and successfully dispatched your first message.

1. Create your account

First, sign up for a free SendAPI account. New accounts get a 3-day free trial — no credit card required. Trial quotas: 100 emails, $0.15 of SMS credit (~10 messages), and one WhatsApp session.

2. Verify your email

Check your inbox for a verification email and click the link. All send endpoints are gated behind email verification — without it, you'll get 403 email_not_verified on every request. The 3-day trial countdown starts the moment you verify.

If you didn't receive the email, request a new one from the dashboard under Account → Verify Email.

3. Obtain your API Key

Once logged in to the dashboard:

Navigate to API Keys in the sidebar.
Click Create Key.
Name your key (e.g., Production Key).
Copy the generated sk_live_... key.

Secure your key

For security reasons, you will only be able to see the secret key once. If you lose it, you will need to revoke it and generate a new one. Store it securely in your .env file.

4. Make your first request

You can interact with the SendAPI using our official SDKs or via any standard HTTP client. For this quick start, we will use cURL to send a test SMS message.

Open your terminal and run the following command, replacing YOUR_API_KEY with the key you just generated, and YOUR_PHONE_NUMBER with your mobile device number (in E.164 format, e.g., +1234567890).

bash

curl -X POST https://sendapi.co/v1/sms/send \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: my-unique-request-uuid-1234" \
  -d '{
    "to": "YOUR_PHONE_NUMBER",
    "content": "Hello from my first SendAPI request! 🚀"
  }'

Use an Idempotency Key in Production

The Idempotency-Key header ensures that if a network error occurs and you retry your HTTP request, we won't charge you twice or send the message twice. Read more about Idempotency →

Inspecting the response

A successful request returns HTTP 200 OK with the message details:

json

{
  "success": true,
  "data": {
    "id": 32,
    "to": "+1234567890",
    "segments": 1,
    "cost": "$0.0250",
    "region": "United States",
    "status": "queued",
    "provider": "telnyx",
    "external_id": "40319d98-8ece-401e-9add-94b696939751",
    "sms_credit_balance": "$0.1250",
    "created_at": "2026-03-09T14:30:00.000000Z"
  },
  "meta": {
    "request_id": "44b5b9cb-6139-47f8-bbc0-e496b0c72ac6",
    "timestamp": "2026-03-09T14:30:00.052104Z"
  }
}

Congratulations! You have successfully integrated SendAPI.

Next Steps

Now that you understand the basics of authentication and request structure, you can explore the specific channel APIs:

Quick Start ​

1. Create your account ​

2. Verify your email ​

3. Obtain your API Key ​

4. Make your first request ​

Inspecting the response ​

Next Steps ​