PPC Percentage Change Calculator

Instantly calculate percentage changes in your paid media metrics - or work backwards from a known % change to find the new value.

What is the PPC Percentage Change Calculator?

Every PPC professional has used one of these in their career. My main issue with what's out there though is the bloat - full of ads, popups and other distractions. This tool is simple, fast and free to use. It does what it says on the tin and nothing else. Calculate your % changes from old numbers to new, or reverse % calculations.

How to Use This Calculator

Whether you're reviewing weekly performance reports or preparing a client deck, percentage changes are the language of PPC. This tool gives you two modes:

Common PPC Scenarios

CPC Tracking

"CPC was £1.42 last week, now it's £1.67 - that's a +17.6% increase."

CPA Reduction

"CPA was £38 and dropped 12% - new CPA is £33.44."

CTR Improvement

"CTR moved from 2.1% to 2.8% - a +33.3% relative improvement."

Budget Change

"Budget was £5,000 and increased 20% - now £6,000."

Why Percentage Changes Matter in PPC

Raw numbers can be misleading. A £0.25 CPC increase sounds small, but if your baseline was £1.00, that's a 25% jump that could blow your budget. Percentage changes normalise comparisons across different metrics, time periods, and account sizes - making them essential for accurate reporting and optimisation decisions.

This calculator is designed for speed. No sign-up, no clutter - just enter two numbers and get your answer. Use the copy button to paste a clean summary straight into Slack, a Google Doc, or a client report.

More PPC Tools

PPC Guidance

Need expert PPC guidance?

Tools help you calculate - but strategy is where results come from. Book a free call to talk through your campaigns.

Book a call with me →