Call Tracking DNI: Dynamic Number Insertion Explained

Dynamic number insertion — DNI — is the deepest form of call attribution available, and it is also the most misunderstood. This page explains how it actually works, what it costs to do properly, who genuinely needs it, and where our own platform deliberately sits instead.

How DNI works

When a visitor lands on your website, a tracking script inspects how they arrived — the campaign, ad group and keyword in the referral data — and swaps the phone number on the page for a unique tracking number bound to that session. When the visitor calls the number they see, the call is logged against the session's attribution: keyword, ad, campaign. A visitor from Google Ads sees one number; a visitor from organic search sees another; a direct visitor a third. The number pool must be large enough to cover concurrent sessions, and the script must swap consistently on every page the number appears.

What DNI is good at — and what it costs

Good at: keyword-level answers. Which search terms generate calls, not just which channel. For businesses optimising individual ads against phone conversions, that is real signal.

Costs: a session-level number pool, a site-wide script, careful handling of numbers baked into images or PDFs, and privacy obligations — session tracking is user tracking, and your privacy documentation should say so. DNI products are priced accordingly, typically well above per-number tracking.

Who actually needs DNI

A simple test: name the decision that would change with keyword-level call data. If the answer is "which of my search ads deserves more budget next month, specifically", DNI earns its keep. If the answer is "radio, print or web?" — the question behind most marketing budgets — per-number tracking answers it at a fraction of the complexity, from $5 a month per number with call data charged per minute.

What we offer, stated plainly

We do not sell DNI. Our call tracking is the per-number model: each campaign or medium gets a fixed number from a pool spanning 40+ regions, call volumes report by number over time, and recording rides along. We would rather sell the simpler model that matches most businesses' real questions than stretch the label. If your test above says you need keyword-level attribution, evaluate DNI vendors against that requirement directly — the platform anatomy checklist applies to them too.

Ready for the per-number model? Pick tracking numbers from the available numbers pool and put the first campaign live.