CPM, CPC, CTR and CPA calculator

Turn campaign totals into the costs and rates that help separate delivery, creative response and conversion performance.

Free to use. No account required.

Enter your numbers

The prefilled numbers are an example. Replace them with your own inputs.

Currency

Labels monetary inputs and results; no exchange-rate conversion.

Ad spend

One currency, one campaign and one reporting period.

Impressions

Times the ad was shown; this is not unique reach.

Link clicks

Keep the click definition consistent across comparisons.

Attributed conversions

Choose one outcome, such as qualified leads or purchases.

Your results

CPM: $20.00; Spend ÷ impressions × 1,000
CPC: $1.00; Spend ÷ link clicks
Click-through rate: 2%; Link clicks ÷ impressions × 100
Click-to-conversion rate: 5%; Conversions ÷ link clicks × 100
Cost per conversion: $20.00; Spend ÷ conversions

How to use the result.

By IG Ad Library · Updated October 23, 2026. Calculations run in your browser.

Start with delivery cost

CPM = spend ÷ impressions × 1,000. It describes the price of exposure. CPC = spend ÷ clicks. A change in CPC can come from a change in CPM, click response or both.

Separate the click from the conversion

CTR = clicks ÷ impressions × 100. Click-to-conversion rate = conversions ÷ clicks × 100. Use click-attributed conversions for this rate; including view-through conversions changes its interpretation. CPA = spend ÷ conversions.

Read the metrics together

A lower CPC with a higher CPA can mean that inexpensive clicks convert poorly. Compare the offer, landing page and audience as well as the opening. Small samples and different attribution windows can make an apparent improvement unreliable.

Worked example

Spend of 1,000, 50,000 impressions, 1,000 link clicks and 50 conversions produce a CPM of 20, CPC of 1, CTR of 2%, click-to-conversion rate of 5% and CPA of 20.

Google Ads: click-through rate definition

Common questions.

Why is a result shown as unavailable?

A rate cannot be calculated when its denominator is zero. Zero conversions means CPA is unavailable, not free. The calculator still shows the other metrics that have enough data.

Can I use all clicks instead of link clicks?

You can, but label that definition consistently. Reactions, profile clicks and link clicks describe different behavior and should not be mixed when comparing creatives.

Apply it to a creative reference.

Study the opening, promise and evidence in a real ad before deciding what to change.