Welcome to SendGrid's Web API v3! This API is RESTful, fully featured, easy to integrate with, and offers support in 7 different languages.

{% anchor h2 %} Hello, World! {% endanchor %}

{% codeblock lang:bash %} curl --request POST
--url https://api.sendgrid.com/v3/mail/send
--header 'Authorization: Bearer YOUR_API_KEY'
--header 'Content-Type: application/json'
--data '{"personalizations": [{"to": [{"email": "your.email@example.com"}]}],"from": {"email": "example@example.com"},"subject": "Hello, World!","content": [{"type": "text/plain", "value": "Heya!"}]}' {% endcodeblock %}

{% info %} SendGrid provides 7 different libraries to help you quickly and easily integrate with the Web API v3.

• C#
• Go
• Java
• NodeJS
• PHP
• Python
• Ruby

{% endinfo %}

{% anchor h2 %} Using the Web API v3 {% endanchor %}

###Authentication

Every API request you make to the Web API v3 must be authenticated by including an Authorization Header with your API Key.

{% codeblock lang:bash %} curl -X "GET" "https://api.sendgrid.com/v3/templates" -H "Authorization: Bearer Your.API.Key-HERE" -H "Content-Type: application/json" {% endcodeblock %}

###Requests

All requests to the Web API v3 must be made via HTTPS. It is a best practice to include the Content-Type: application/json header in all of your requests.

The Web API v3 is completely RESTful and accepts GET, POST, PUT, and DELETE requests, depending on the resource.

{% codeblock lang:http %} POST https://api.sendgrid.com/v3/templates/ HTTP/1.1 Content-Type: application/json

{ "name": "new template name" } {% endcodeblock %}

###Responses

The Web API v3 provides a selection of response codes, content-type headers, and pagination options to help you interpret the responses to your API requests.

Your Request {% codeblock lang:http %} GET https://api.sendgrid.com/v3/resource HTTP/1.1 {% endcodeblock %}

Our Response {% codeblock lang:http %} HTTP/1.1 200 OK Content-Type: application/json

{ "foo": "bar", } {% endcodeblock %}

###Rate Limits

Depending on the endpoint you are trying to reach, it will have a specific number of allowed requests per refresh period. Once this threshold has been reached, we will return a status code 429 response.

###Errors

Sometimes your API call will generate an error. Every response to an API call that generates an error will include an error code, the reason for the error, and an error message to help you debug your request.

For an example of a generic error message, click here. For a list of specific errors that may be returned when using the v3 Mail Send endpoint, click here.