Twilio

API

Cloud API for SMS, WhatsApp, voice calls and user verification

Price: Free trial, then pay per use
Access: Account SID and Auth Token

About

Twilio is a communications API for sending SMS and WhatsApp messages, making and receiving phone calls, and verifying users with one-time codes. It suits apps that reach people by phone. Every message and minute is billed, and prices vary by country.

What you can do with it

Send SMS and WhatsApp messages from your app
Add inbound and outbound voice calls to your web or mobile app
Verify users with one-time codes sent by SMS, voice or email

Get started

Sign up for a Twilio trial account
Verify a recipient and note your trial phone number
Copy your Account SID and Auth Token from the Console

Example

curl -X POST "https://api.twilio.com/2010-04-01/Accounts/$TWILIO_ACCOUNT_SID/Messages.json" \
  --data-urlencode "From=+15557122661" \
  --data-urlencode "Body=Hi there" \
  --data-urlencode "To=+15558675310" \
  -u $TWILIO_ACCOUNT_SID:$TWILIO_AUTH_TOKEN

Details

Hosting: Hosted service
Available in: Worldwide
Official SDKs: C#, Java, JavaScript/TypeScript, PHP, Python, Ruby, Go
MCP server: None
Works with: WhatsApp