Use Cases

How to Build: Call Tracking

Use Twilio APIs to track volume and duration of calls, get insights about who called, and what was said.

Call Tracking helps you measure the effectiveness of different marketing campaigns.

Step 1

Obtain Twilio phone numbers

Purchase a pool of phone numbers from the Twilio self-service portal or the Twilio Phone Number API. You can search for phone numbers within a specific country and area code.

Step 2

Map Twilio phone numbers

Choose and implement your phone number allocation strategy. The most typical is a 1:1 mapping between an agent and a Twilio number. In this example, an advertiser’s number is mapped to the Twilio phone number.

Step 3

Implement counters

Set up counter linked to the webhook that Twilio sends your app to count the number of incoming calls.

Step 4

Publish Twilio phone numbers in your ads or web pages

You are now ready to publish the Twilio phone numbers on your ad, web page, or any other content.

Step 5

Interested buyers call the listed number

When the listed number is called, Twilio receives the call and sends a webhook to your web server. The counter associated to the Twilio number will be updated.

Step 6

Your web server returns the mapped phone number

Your web server looks up the advertiser’s private phone number mapped to the Twilio number and returns a TwiML to that advertiser’s number. Twilio initiates a call between the buyer and that advertiser.

Want to learn more?

Get started with Voice

Take charge of your phone calls with Twilio.

Read the docs

Build Call Tracking

Learn how to assign a unique phone number to your ads.

Explore tutorial

Per Minute Pricing

See local and toll-free pricing to send and receive calls.

View pricing

The Twilio Advantage

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Many channels

Use the same platform you know for voice, SMS, video, chat, two-factor authentication, and more.

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