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Build and Test Your Application

Welcome to the "Build and Test Your Application" section of the Twilio SendGrid Onboarding Guide. When you complete this milestone, you'll be able to communicate with your customers whenever you need and at whatever scale you require. We encourage you to complete all the steps presented here. In the evolving world of email, a careful roll-out will help you avoid costly and time-consuming remediation.

In this Onboarding Guide section, your team will:

  • Implement your email program architecture by setting up a parent account and creating optional Subusers.
  • Authenticate your domain and configure all settings for optimal deliverability.
  • Build and test your Email API or SMTP integration.
  • Complete an IP warm-up to establish your sender reputation with email service providers.

We designed these steps to facilitate a team implementation process, including both developers and non-developers. Each step and its associated action(s) is marked as required, recommended, or optional to help you navigate this guide efficiently while providing all the information needed to develop a solid email program.

You'll perform many of the following steps in the Twilio SendGrid user interface (UI). However, some steps are more technical than others, and we've noted when you may benefit from having a developer available.

Step 1: Account Set-Up | required

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Twilio SendGrid offers three paid plans(link takes you to an external page): Essentials, Pro, and Premier. Each plan provides a set of features and a range of sending capacities. In this step, you'll choose an upgraded plan (if you haven't already) that will give you the capability to send up to a certain volume of monthly messages.



Some of the following optional steps and actions such as managing Subusers and adding dedicated IP addresses will require a Pro or Premier plan.

Next, you'll build your parent account and ensure that your key team members have the right level of access to that parent account. Finally, you'll add any additional IP addresses needed to send at your initially anticipated volume. These tactical building blocks will lay the groundwork for everything else you are about to do.

Navigate to the linked documentation and resources below to complete the actions in this step.

ActionRequirement Level
Create a new account or login to your account.(link takes you to an external page)Required
Enable Two-Factor Authentication.Required
Upgrade your plan to ensure that you can send at the volume you need.Required
Assign Teammates to collaborate with and set their permissions.Recommended
Add additional IP addresses.Optional

Subusers vs Teammates

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In step one of this section, you could have optionally created Teammates, which are different from Subusers. Teammates are people who have permissions to access either a parent account, a Subuser, or both. Subusers are child accounts of the parent account.

You can think of Subusers like subaccounts. Each Subuser account is its own email ecosystem with isolated contacts, templates, suppressions, and data. Subusers feed off their parent account email credits, and all billing rolls up to the parent account. Subusers can have their own Teammates who can access only the Subuser accounts to which they are assigned.

Navigate to the linked documentation and resources below to complete the actions in this step.

ActionRequirement Level
Create one or more Subusers.Recommended

Step 3: Complete sender authentication | required

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Sender authentication shows email providers that Twilio SendGrid has your permission to send emails on your behalf. The sender authentication process is composed of three steps: domain authentication, link branding, and reverse DNS (rDNS).



To complete domain authentication, you must be able to add DNS records to your DNS host.

To designate Twilio SendGrid as an allowed sender on your domain, you will add DNS records provided by Twilio SendGrid to your DNS entries using your DNS provider (e.g. GoDaddy, Rackspace, Cloudflare, Route53, etc.). These entries are known as SPF and DKIM records. To better understand how these records work, see our SPF and DKIM documentation.



To complete reverse DNS, you must be able to add DNS records to your DNS host. rDNS is necessary only for accounts using dedicated IP addresses.

Reverse DNS (rDNS) associates your dedicated Twilio SendGrid IP address(es) with your authenticated domain. To complete rDNS, you will place an A record on your domain for the IP address provided by Twilio SendGrid. When a mailbox provider looks up your A Record on your sending domain, they will see your Twilio SendGrid IP address. When they look at your IP address, they will see the rDNS matching your A Record. This circular check tells email service providers (ESPs) and email recipients that your email is legitimate and trustworthy.

Navigate to the linked documentation and resources below to complete the actions in this step.

ActionRequirement Level
Set up domain authentication.Required
Assign Subusers to an authenticated domain.Required when using Subusers
Set up link branding.Recommended
Enable reverse DNS.Required when using dedicated IP addresses

Step 4: Configure settings | required

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The set of actions in this step pertain primarily to using the Twilio SendGrid Email API. You will benefit by having a developer available for this step.

API keys and the Twilio SendGrid Event Webhook are both powerful parts of the Twilio SendGrid API. API keys allow you to quickly control who has access to what in your email application. Our Event Webhook provides the data necessary to understand how users are engaging with your communications.

Proactively managing your global and group unsubscribes will improve your reputation with ESPs because you'll be automatically emailing users who are more likely to engage with your content. Each of these settings is key to the optimal functioning of your application.

Navigate to the linked documentation and resources below to complete the actions in this step.

Step 5: Integrate and test your mail send | required

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It's time to integrate the Mail Send API and test your application. Having a developer available will be beneficial.

When sending email with Twilio SendGrid, you can use either the Email API, which sends mail over HTTP and provides a modern developer experience, or route mail through our SMTP service.

When using the Email API, you also have access to Twilio SendGrid's helper libraries, allowing you to quickly integrate with the API using C#(link takes you to an external page), Go(link takes you to an external page), Java(link takes you to an external page), Node.js(link takes you to an external page), PHP(link takes you to an external page), Python(link takes you to an external page), or Ruby(link takes you to an external page).

You can also use our Dynamic Template system to send visually appealing email designs that are easy to customize both for your brand and to the individual recipients receiving them.

Navigate to the linked documentation and resources below to complete the actions in this step.

When you complete the steps above, you'll have a working email application. You will have an IP with a strong reputation, and your emails will be landing in your recipients' inboxes with minimal filtering.

Your email application should now have:

  • A parent account
  • Subusers for any unique use cases or customers
  • Teammates for each parent and Subuser
  • An authenticated domain
  • API keys
  • A Twilio SendGrid API or SMTP integration
  • At least one warm IP address

Your email application may also have:

  • Enabled global unsubscribe settings
  • Enabled group unsubscribe settings
  • Enabled link branding

Next, Monitor and Optimize

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