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SMS

Send text messages worldwide via API or web platform.

Viber

Deliver rich, branded messages with media through API or intuitive web tools, with failover support.

AUTHENTICATION

HLR & MNP Lookup

Real-time network and number checks for precise delivery.

Verify API

Enable multi-factor authentication on any channel, with fallback options.
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SMS.to Blog

How to Send SMS From Your App: Node.js, Python and PHP Examples

Copy-ready Node.js, Python and PHP code for sending SMS through the SMS.to API, receiving delivery

“Absent Subscriber” and 12 Other SMS Error Codes Explained

"Absent subscriber" means the network knows the number but cannot reach the handset right now.

What Is a Text Message API? How It Works, With Code

A text message API lets your software send SMS with a single HTTP request. Here

Free SMS API for Developers: What’s Really Free (and What Isn’t)

Most "free SMS APIs" are free to try, not free to run. This guide explains

What Does “Invalid Number” Mean in SMS Delivery Reports?

"Invalid number" means an SMS could never reach the destination as addressed. Here are the

SMS Glossary: 28 Messaging Terms Explained (SMPP, DLR, HLR…)

SMPP stands for Short Message Peer-to-Peer. This glossary defines 28 SMS terms, from delivery reports