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# Getting started with SMS

> Sending your first SMS message

## 1. Get a number

First, [sign up](https://app.pinnacle.sh/auth/sign-up) for an account. To get started with testing, obtain a free sandbox number by navigating to **Development > Sandbox numbers** in the left sidebar.

> **Note**
>
> You can purchase production numbers later when you're ready to go live

![Get a number](https://server.trypinnacle.app/storage/v1/object/sign/vault/3/74609dd7-a565-4cfd-9d08-c051334ee1bc/7afa2262ef49fbb3c5a5df627d8051c3.png?token=eyJraWQiOiJzdG9yYWdlLXVybC1zaWduaW5nLWtleV9hOGI0YTI0NC00NzY4LTRhOTktYWI4MS1iNmZhNTZhNGQyZWYiLCJhbGciOiJIUzI1NiJ9.eyJ1cmwiOiJ2YXVsdC8zLzc0NjA5ZGQ3LWE1NjUtNGNmZC05ZDA4LWMwNTEzMzRlZTFiYy83YWZhMjI2MmVmNDlmYmIzYzVhNWRmNjI3ZDgwNTFjMy5wbmciLCJpYXQiOjE3NjA3MzI1ODgsImV4cCI6MzE3MTIwNzMyNTg4fQ.9imj3zVIYLbWP8Zf_X8lzirA0Cw2pipxa48UrzAUqG8)

Click **Get number** and enter a phone number to whitelist—for security purposes, sandbox numbers can only send messages to whitelisted numbers. After clicking **Get number**, you'll see a card displaying your new sandbox number. Click the phone icon on the right side of the card, then select the smartphone icon and enter the 4-digit PIN that was texted to your device. Once verified, you can copy your sandbox number by hovering over it on the card.

## 2. Get credentials

Navigate to **Development > API Keys** and click **Create API Key**. Give your key a descriptive name, then click **Create**. Once generated, copy your new API key and store it securely.

## 3. Select a language

### SDK Guides

#### [Python](/quickstart/sms/python)

#### [TypeScript](/quickstart/sms/typescript)

#### [Ruby](/quickstart/sms/ruby)