---
title: What Are API Keys, and How Are They Used on SMSGatewayCenter?
description: "**API keys** are essential for secure communication with **SMSGatewayCenter**’s Restful API, enabling you to send SMS programmatically. Here’s an overview of API keys and their usage: ## **What Are API Keys?** - API keys are unique codes used to authenticate…"
url: "https://www.smsgatewaycenter.com/blog/kb/api-keys-usage/"
updated: "2025-05-17"
category: Users / API Key
---

# What Are API Keys, and How Are They Used on SMSGatewayCenter?

**API keys** are essential for secure communication with **SMSGatewayCenter**’s Restful API, enabling you to send SMS programmatically. Here’s an overview of API keys and their usage:

## **What Are API Keys?**

- API keys are unique codes used to authenticate and authorize requests to SMSGatewayCenter’s Restful API.
- They act as login credentials, ensuring only authorized users can access the API for sending SMS.

### **How to Use API Keys on SMSGatewayCenter**

- **Include in Request Header**: Add the API key to the request header for authentication when making API calls.
- **Use with UserID**: Include your “userid” parameter along with the API key as login credentials in your API requests.
- **No Password Required**: When using an API key, you don’t need to provide a password parameter, simplifying the authentication process.
- **Example Use Case**:
- To send an SMS via the API on May 17, 2025, at 03:20 PM IST, your request might look like this:
  - Header: `Authorization: Bearer your_api_key`
  - Parameter: `userid=your_userid`

#### **Best Practices**

- Keep your API key confidential to prevent unauthorized access.
- Store the API key securely in your application, avoiding hardcoding in source code.

API keys enable secure and efficient SMS sending via **SMSGatewayCenter**’s Restful API. For assistance, contact our support team.

### More Related Articles

- [Why Don’t I Need a Password When Using an API Key on SMSGatewayCenter?](https://www.smsgatewaycenter.com/blog/kb/api-key-authentication-no-password/)
- [What Happens If I Regenerate My API Key on SMSGatewayCenter?](https://www.smsgatewaycenter.com/blog/kb/api-key-regeneration-impact/)
- [What Security Best Practices Should I Follow When Using API Keys on SMSGatewayCenter?](https://www.smsgatewaycenter.com/blog/kb/api-key-security-best-practices/)

Found this useful?[Add as Preferred Source on Google](https://www.google.com/preferences/source?q=smsgatewaycenter.com)