Dynamic Number Insertion (DNI): What It Is & Why You Need It

Tracking web conversions is easy. Since everything is online, Google's GCLID can tie the conversion directly back to the ad click it came from. Tracking calls, on the other hand, is a bit harder: after clicking your ad, someone has to physically pick up the phone and dial your number, breaking that neat chain of online tracking data.

Dynamic number insertion (DNI) solves this problem by automatically swapping your website's phone numbers with unique tracking numbers that change based on who’s viewing them and what marketing channel they came from. When visitors call your business, they’ll call via a tracking number that marketers can then tie back to the marketing source of the call.

This comprehensive guide breaks down everything you need to know about dynamic number insertion:

• What DNI is and how it works
• The types of data it captures
• Key benefits and use cases
• Implementation best practices
• How to use DNI data to improve marketing ROI

What Is Dynamic Number Insertion?

Dynamic number insertion is a call tracking technology that displays a unique tracking number to each website visitor. When someone lands on your site, DNI replaces your business number with one from a pool of tracking numbers. Each visitor sees their own unique number, letting you capture complete data about how they found and interacted with your site.

For example, let's say two potential customers visit your website simultaneously:

• Sarah lands on your site and sees tracking number A
• Mike visits right after and sees tracking number B

When you get a call from tracking number A, your call tracking platform can tie that call back to the click-through for the landing page displaying tracking number A, as well as the marketing source for that click.

Once Sarah and Mike finish their calls, those numbers become available for new visitors. This rotating pool system, combined with sophisticated visitor tracking, captures the complete marketing journey behind every call—from first click to final conversation.

How Does DNI Work?

There are three main ways to implement call tracking with DNI:

Keyword-Level Tracking with Dynamic Number Pools (Recommended)

Keyword-level tracking uses rotating pools of numbers assigned to individual visitors, making it the most comprehensive way to implement DNI. This method captures complete marketing data including source, medium, campaign details, and keywords and enables enhanced conversion tracking and optimization within your ad platform.

Most businesses choose keyword-level tracking with dynamic number pools since it provides the most comprehensive data. Here's how it works:

1. Visitor Detection: When someone lands on your website, the DNI script creates a unique visitor profile using first-party cookies and tracking parameters
2. Number Assignment: The system assigns that visitor a unique tracking number from your pool, ensuring no active visitors see the same number
3. Data Collection: When someone calls their assigned number, WhatConverts captures over 70 data points including:
   • Source/medium
   • Campaign details
   • Keywords
   • Landing pages
   • Lead pages
   • User data (IP, browser, device)
   • Full visitor journey

This visitor-level tracking lets you trace every call back to the exact marketing that drove it. The system intelligently rotates numbers to maintain accurate tracking even during high-traffic periods.

Marketing Source Tracking

This simpler approach assigns one tracking number per marketing source, so every person who visits your site from a particular marketing channel will see the same tracking number. While easier to set up, it provides less detailed data and cannot track keywords or pass conversion data to ad platforms. The tracking is limited only to marketing sources you explicitly configure, and if more than one visitor from the same channel calls at the same time, you won’t be able to trace each call back to the specific ad click they came from.

Offline/Third Party Site Tracking

Designed for non-website marketing channels, this method uses dedicated numbers for offline marketing like flyers, magazine ads, and direct mail. It tracks basic call data including caller ID, duration, and recordings, making it ideal for measuring offline campaign performance. Businesses that advertise both on and offline can combine this method with either of the other two above.

Key Benefits of Dynamic Number Insertion

DNI unlocks a host of benefits for marketers. Most importantly, you can bridge the gap between an offline conversion action (phone call) and the online marketing that drove it. However, there are several other notable benefits as well:

See Both Individual & Aggregate Lead Data

DNI doesn't just tell you how many calls came from each marketing channel—it lets you drill down into individual lead data while also seeing the big picture. For each caller, you can see their complete journey including which ads they clicked, pages they visited, and keywords that brought them in.

Then you can zoom out to spot trends across all your leads, helping you identify which marketing consistently brings in the best prospects.

What Kind of Data Can You Track with DNI?

The data you can track with DNI depends on which platform you use.

Some let you see a massive amount of attribution data for every single lead (e.g., John Doe searched “structural engineer” and clicked on ad variation #1).

Others only show you a tally (e.g., Ad Variation #1 brought in 25 leads).

For instance, WhatConverts shows you individual lead data across 70+ data points, including:

• Source
• Medium
• Keyword
• Landing page
• Contact name
• Email address
• Caller location
• Answer status

You can also see and report on this data across all your leads to get high-level insights.

See the WhatConverts API documentation for a list of all the lead data collected.

Optimize for Lead Quality, not Quantity

DNI tracking allows you to tie each ad click to your site to the specific caller they came from. That means you can see which ads are bringing in good leads and which are bringing in junk.

Not only can you see that information, but you can also send that information back to Google Ads. Instead of bidding on the keywords that get the most clicks, that enhanced data will train its algorithm to target the clicks that came from quality leads.

One Step Further with WhatConverts: Optimize for Revenue Earned

WhatConverts isn’t actually a call tracking platform—it’s a lead tracking platform that also offers DNI call tracking. Its additional lead tracking features include the ability to add quote values and final sales values to each of your individual leads and use that data to gain additional insights on your leads. So not only can you optimize for lead quality, but you can actually optimize for dollar amounts in revenue.

For example, let’s say you’re looking at your ad performance by keyword. Evaluating keywords based on how many qualified leads they captured is a good starting point, but in WhatConverts, you can actually see which keywords are making you the most money:

Faster, More Accurate Lead Qualification

Marketers need three pieces of information to qualify a lead:

• Who they are (real vs. spam, new vs. returning)
• Where they’re from (Google Ads, organic search, social media referrals)
• What they want (what product or service they’re interested in)

Dynamic number insertion is what makes it possible to determine where a lead is coming from. Most DNI call tracking platforms also offer voice recordings and call transcripts, so instead of wading through messages one at a time, you can scan through leads and quickly see which calls hung up right away, which were obviously spam, and which were potential customers that mentioned their interest in one of your products or services.

For example, the WhatConverts Lead Details screen shows you who the caller is (name, contact details, location, etc.) and what they want using the call recording and transcription:

With this added data, you can easily qualify your leads and even add a quote or sales value based on what they’re interested in.

What Can Marketers Do with DNI Tracking?

Since DNI enables marketers to get clear attribution for their offline phone calls, using it opens up the door to countless opportunities.

With it, marketers can:

• Give clients more accurate performance updates
• Optimize PPC campaigns for maximum value
• A/B test campaign elements like ad copy, landing page design, CTAs, etc.
• Better understand how qualified the leads are that their marketing generates

DNI & Lead Tracking Case Studies

The case studies below show how marketers can use DNI and lead tracking to improve their marketing and grow their agencies.

 

• One PPC Shift, Massive Results: Agency Earns 42% YOY Growth With 3-Point Strategy
• Law Firm Marketing Agency Turns Client’s Doubt into a 9X ROI Win
• Path to $1M MRR: Agency Shifts from Vendor to Partner w/ Advanced Reporting

How to Set Up DNI with WhatConverts

Setting up dynamic number insertion in WhatConverts takes just four steps.

Step 1: Create Your Account

If you don’t have an account already, you start your free 14-day trial.

Step 2: Add Your Tracking Code

This is the JavaScript snippet that replaces your website’s phone number with a tracking number.

You can either use the handy WordPress plugin here or you can put it into the header section of your webpages manually or using Google Tag Manager.

Help Center: Adding WhatConverts Script to Your Site

Step 3: Set Up Your Numbers

This step takes just a minute.

1. Navigate to the Tracking menu at the top of the page, then select Calls and Phone Numbers.
2. Click + Add Dynamic Pool.
3. Follow the setup wizard to pick out your tracking numbers, port them to your website, and add any extra features you find valuable.
   

For a more detailed explanation, check out our Help Center article.

Step 4: Start Getting Insights

Once your numbers are set up, all that’s left for you to do is analyze the data.

There are two ways to do that:

• Lead Manager – Useful for checking realtime data. It also shows individual lead data so you can qualify, categorize, and value leads.
• Reporting – Great for high-level insights and client reporting.

From there, you can spot opportunities and optimize your marketing for even greater ROI.

Wrapping Up

Dynamic number insertion is a powerful tool for marketers, and one made even more useful when combined with a lead tracking platform.

With it, marketers can prove and grow their ROI by making better marketing decisions based on real data.

Ready to get the most from DNI? Start your 14-day WhatConverts trial today!