At Harvard, we’re big fans of TextMarks. Not only have students been using SBOY [shuttle text service] for years to get shuttle schedules on demand, the underlying TextMarks API is so simple that we’ve introduced it in CS50 to teach students how to use APIs.
- David J. Malan, Harvard University
  CS 50: Intro to Computer Science I

The easiest to use, most reliable SMS API available:

TextMarks Text Message API

  • Clear documentation and a commitment to excellent customer support.
  • No speed limit. Others limit you to 1 per second.
  • No long term contracts, no hidden fees, and simple pricing.
  • No ads or forced headers. Control all 160 characters of your message.
  • List management abstractions. Much more than a simple gateway.
  • Stable at high speeds/volume. Your messages processed on time.

Inbound API
Text Message Request/Response

Provide on-demand access to information via text message with your own “SMS Auto-Responder”.

Users send a text message beginning with your keyword to our shared shortcode 41411, our servers HTTP request to your servers (a "callback" or "web hook"), your scripts look up the info requested and respond, and we instantly forward that to the user as another text message.

Click to learn more about SMS Auto-Responders

Outbound API
Send Text Messages by API

Notify your users by text message. Make an HTTP request to our API server and we handle the rest, with near instant delivery.

Send to individuals or groups. Users can join your list by texting your keyword to our shared shortcode 41411. We handle carrier compliance and group membership so you can focus on your application and business.

Click to learn more about SMS sending API

Advanced API
Advanced API Integrations ... (Click to learn more)

The “Send Text Messages by API” above is part of our larger API, ready for you to access more data, manage keywords, statistics, group membership, and more -- enough to build your own white label version of the TextMarks service!

Did you know...

Did you know that the entire web site is built on top of our own API?
That's how powerful and reliable it is. If our API is down, we're down.

Our API is built on modern lightweight web standards like basic HTTP and JSON. Our documentation and tools let you discover what's possible and make calls in your browser without writing a single line of code. Our protocols are open and easy to implement, and we offer production-ready client libraries for Python, PHP, Java, and .NET.

More Information

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