Why is Gmail API better or worse than traditional SMTP?Â
Email protocol used
Simple Mail Transfer Protocol (SMTP) is a set of rules for sending emails either from the sender to the email server or between servers. Most email service providers use SMTP to send and POP3/IMAP4 to receive emails. To learn more about these protocols, you can read our IMAP vs. POP3 vs. SMTP blog post. Google also provides the Gmail SMTP server as a free SMTP service. Application Programming Interface (API) is an interaction channel used by apps, platforms, and codes to reach each other. With Gmail API, you can send emails using only HyperText Transfer Protocol (HTTP), a set of rules that defines how messages are formatted and transmitted.
How are emails sent?
You can call the API from the app to communicate with an email service that is used to send emails from another server.Â
For SMTP, a client establishes a TCP connection to the SMTP server and transfers an email. After authorization, the server sends the email to the recipientâs SMTP server, which, in turn, forwards it to the IMAP4 or POP3 server. Client and server communicate with each other using SMTP commands and responses.
Authentication
Gmail API uses open authentication (Oauth2), which only lets you request the scope of access you need. SMTP provides full access to the account using client login and password SMTP authentication.
Quota
The usage limit of Gmail API is one billion quota units per day. Each method requires a particular number of quota units. For example, a drafts.create
is 10 units and a messages.send
is 100 units. Gmail API enforces standard daily mail sending limits. Also, keep in mind that the maximum email size in Gmail is 25MB.
SMTP or API?
Each option has its own pros and cons. SMTP is a widely adopted and easy-to-set-up solution to send emails. Moreover, you donât need any coding skills to handle stuff. Also, you can benefit from using a fake SMTP server such as Mailtrap as a playground for safe email testing.
Besides, it is a great option to automate processes and provide a wide range of functionality for the app. Also, API can boast an extra level of security, which is crucial if you deal with sending sensitive data in emails.
If you want to use email API with easy onboarding process, comprehensive stats and reliable support, try Mailtrap Email API.
I hope you enjoyed reading our guide on how to send emails with Gmail API using GoLang, PHP, Python, JavaScript and more that was originally published on Mailtrap blog.