Avatar photo Alex Thompson
Jul 3, 2024

Dynamic number insertion (DNI) is a marketing tool that swaps out your website’s phone number with tracking numbers. These tracking numbers change based on who’s viewing them and where they came from (e.g., Google Ads, organic search, referral traffic).

DNI is a key call tracking feature because it ties offline phone calls to online marketing sources, letting marketers understand which channels are driving phone calls.

In this guide, we’ll break down the fundamentals of this foundational marketing concept:

  • How does dynamic number insertion work?
  • What are the benefits of DNI?
  • What can marketers do with DNI?
  • How do you set up dynamic number insertion?

How Does Dynamic Number Insertion Work?

The Ultimate Guide to Call Tracking Software
Top 9 tools rated from 3K+ G2 reviews

    Dynamic number insertion uses a small snippet of JavaScript to switch your website phone number with a unique tracking number. These numbers are either unique to a channel (Google Ads, Facebook, Bing, etc.) or to the individual user.

    When combined with marketing data stored in cookies, DNI lets you see what online marketing is bringing in offline calls.

    For example, let’s say your website gets two visitors at the same time:

    • John Doe – Came from Google Ads
    • Jane Doe (unrelated) – Came from Google organic

    Each visitor’s marketing data is stored in first-party cookies so you can see their marketing source.

    If you’re using DNI, John will see tracking number #1 when he calls for a quote, while Jane will see tracking number #2.

    With call tracking software, you can tie each number back to the caller’s marketing data— you can see John came from Google Ads while Jane came from Google organic.

    By tying this data together, you can see:

    1. Marketing data (source, medium, keyword, landing page) for individual phone call leads
    2. Marketing data across all phone call leads.

    With this data at your fingertips, you can gather insights, optimize your budget, and make better marketing decisions.

    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.

    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 some other notable benefits as well.

    Better Understand What Marketing Works

    A marketer’s job is to maximize the number of quality leads generated while minimizing the cost it takes to bring in those leads.

    To do that, you need to know how effective each marketing channel is.

    Dynamic number insertion lets you see where calls are coming from down to the channel, campaign, ad, and even keyword. And with that data, you can determine which marketing is producing the most leads.

    Revenue Earned > Lead Quantity

    Lead quantity is a good starting point for tracking marketing effectiveness. But KPIs like revenue and return on investment (ROI) are much more defined measures of success.


    Advanced lead tracking platforms let you tie value-based metrics (like sales value) back to marketing data like keywords and campaigns. So instead of seeing how many calls a keyword generated, you can see how much revenue it brought in.


    Here’s what that looks like in WhatConverts:

    Clearer Optimization Opportunities

    With only so much budget to work with, marketers need to use every dollar to maximize the value their campaigns generate.

    Dynamic number insertion helps marketers use the attribution data it provides to spot and optimize their budgets based on low- and high-performing marketing.

    For instance, let’s take the example above of an agency running PPC for a home inspection business. Again, here’s what their keyword breakdown looks like by sales value earned:

    Now, it’s clear the keyword “house inspection services” brings in the most revenue. You might be tempted to siphon the budget away from some of the low-earners and put that into this keyword instead.

    However, what if we tweak the data to show value per lead?

    Now the data tells a much different story. The keyword “mold test” brings in $907.80 per lead, while “house inspection services” leads are only worth $169.58 a piece.

    With this new data, you might try experimenting with adding more budget to your “mold test” keyword to bring in more high-value leads.

    This kind of insight would be impossible to spot without dynamic number insertion.

    Easier Lead Qualification

    Dynamic number insertion (when used with a lead tracking platform) also makes it easier to qualify the leads your marketing generates.

    Marketers need three pieces of information to qualify their leads:

    • Who they are (real vs. spam, new vs. returning)
    • Where they’re from (Google PPC, organic search, social channel referral)
    • What they want (which service or product are they interested in)

    Without DNI, determining the where would be impossible. And with a lead tracking platform you can understand the who and what before qualifying.

    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.


    How Do You Set Up Dynamic Number Insertion?

    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 can start your free 14-day trial from the trial button above.

    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 put it into the header section of your webpages manually.

    Help Center: Adding WhatConverts Script to Your Site

    Step 3: Set Up Your Numbers

    This step takes just a minute.

    Just pick your numbers, plug in where to send them, and add any extra features you find valuable.

    All in all, the process takes under a minute to set up.

    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!

    Read WhatConverts reviews on G2

    Avatar photo
    Alex Thompson

    Alex Thompson is a professional copywriter and content writer with a passion for turning complex ideas into digestible, educational content that keeps readers engaged. He specializes in content marketing, SEO, and B2B marketing.

    Get a FREE presentation of WhatConverts

    One of our marketing experts will give you a full presentation of how WhatConverts can help you grow your business.

    Schedule a Demo
    ready to get marketing clarity?

    Grow your business with WhatConverts

    14 days free trial Easy setup Dedicated support
    G2 Users Love Us Badge
    G2 High Performer Badge
    G2 High Performer Small Business Badge
    G2 Momentum Leader Badge
    G2 High Performer Europe Badge