The Easiest to Use, Most Reliable SMS API

We built on it, so if the API is down, we’re down

At Harvard, we’re big fans of TextMarks. Not only have students been using SBOY 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: Introduction to Computer Science I

Why use our text messaging APIs?

TextMarks SMS APIs allow you to send and receive text messages from your web or enterprise application using our shared shortcode.

Unlike SMS e-mail gateways which add ugly headers, limit your delivery rate, and can take hours to deliver your messages, our API gives you a reliable direct conduit to your users' mobile phones.

With our group management functionality, group text broadcast, and the ability to easily handle and respond to incoming SMS messages with scripts on your own server, you have the perfect text messaging solution for your app.

Use as little or as much of our API services as you need. Read more and see how TextMarks SMS API is just what you're looking for.

TextMarks Press Buzz

“This is an excellent idea.”
“There are endless uses for this technology.”
“Create your own text message distribution center with TextMarks.”

New — Developer Free Trial! 100 free messages, free keyword for 6 months.

Just contact once you sign up for your account.

The easiest, least expensive way to SMS-enable your application

Key features

  • Send and receive SMS messages from our short code 41411.
  • Fully tested and documented API, with clients available in popular languages.
  • You can be up and running in a matter of minutes.
  • No contracts, no hidden fees, simple pricing.
  • No speed limit for paid plans - send as many messages as you need to. Others limit you to 1 per second.
  • Control the full 160 characters of your message. No ads or forced headers.
  • High level subscription & group messaging features provided. No need to build this basic functionality other simpler low level gateways require.
  • Stable at high speeds. Millions of messages per week are sent through our API.

API Services

We offer three main services for developers looking to easily integrate SMS/text messages into their applications and web sites. They are listed here from simplest to most advanced, with more information on each below.

Request/Response Integration

How it works

  1. Users send a text message to 41411 starting with your keyword.
  2. TextMarks servers make an HTTP request to any callback URL you define.
  3. Your custom script runs on your own server and generates a response.
  4. The response is sent back to requesting user as a text message.

Recommended programming experience

Anybody with basic web programming experience should be able to execute this type of integration.

Additional notes

Once a user engages with your keyword, they don't necessarily have to keep sending the keyword with each request. You can provide multiple choice questions or other interactions by telling the user e.g. "Rply A for cookies. Rply B for pizza." and the user need only reply with "A" or "B". Text STATEINFO to 41411 for an example of how simple and powerful this contextual response feature is.

Asynchronous Automated Messaging

How it works

  1. You integrate our API client into your software (or call our API directly if you wish).
  2. Users subscribe to your TextMarks keywords (e.g. by texting your keyword to 41411).
  3. At any time you wish, you call our API to send a text message to an individual subscriber or blast to all of your subscribers at once.

Recommended programming experience

For this type of integration, you should be somewhat familar with calling public web services. We offer API clients for common languages (PHP, Python, Java).

Advanced TextMarks SMS API Integration

How it works

TextMarks powerful API provides programmatic access to practically everything you can do on our website. Clients have built entire complex text-messaging applications on top of our API. Even this web site itself uses our API!

Recommended programming experience

Only experienced systems programmers should undertake complex TextMarks integrations. We recommend starting with Asynchronous Automated Messaging (see above), which is a subset of the full API package, and then building from there.

Additional Information and Documentation