> Index of Phersa pages for AI agents: https://phersa.com/llms.txt

# CPM Calculator

Calculate the CPM of an Instagram or Facebook ad from its cost and impressions, or turn it around: what a number of impressions will cost, or how many a budget buys. Add clicks and reach for CTR, cost per click and frequency. For creators and AI persona pages that run their own ads.

## How to use the CPM Calculator

1. Pick what to find: CPM, Cost or Impressions.

2. Type the other two, from Ads Manager or from your plan. Add clicks and reach if you have them.

3. Read the result with CTR, cost per click and frequency. Compare it with your past campaigns.

## The CPM formula, three ways

CPM is the cost of 1,000 impressions. Meta defines it as the average cost for 1,000 impressions, and an impression as a time your ad was on screen. Any one of the three numbers comes from the other two:

| To find | Formula | Made-up example |
| --- | --- | --- |
| CPM | cost ÷ impressions × 1,000 | $60 ÷ 15,000 × 1,000 = $4.00 |
| Cost | CPM × impressions ÷ 1,000 | $4 × 40,000 ÷ 1,000 = $160 |
| Impressions | cost ÷ CPM × 1,000 | $100 ÷ $4 × 1,000 = 25,000 |

A budget buys the impressions shown only if the CPM holds. CPM moves from one campaign to the next, so treat a budget plan as a rough guide.

## Impressions, reach and frequency

Impressions count every time the ad was on screen. Reach counts the accounts that saw it at least once. One person who saw your ad three times is three impressions and one account reached.

- **Frequency** = impressions ÷ reach: how many times, on average, each account saw the ad.
- **Cost per 1,000 accounts reached** = cost ÷ reach × 1,000. It is always equal to or higher than CPM, because reach is never more than impressions.

**Made-up example:** 15,000 impressions on a reach of 9,000 is a frequency of 1.67. At a cost of $60, that is $6.67 per 1,000 accounts reached, next to a $4.00 CPM.

## CTR and cost per click from the same numbers

Add clicks and the calculator shows two more numbers:

- **CTR** = clicks ÷ impressions × 100.
- **Cost per click** = cost ÷ clicks.

Ads Manager reports more than one kind of click. Link clicks count only clicks on links. If what matters is people reaching your offer, use link clicks. With made-up numbers, 180 link clicks on 15,000 impressions is a 1.2% CTR, and $60 ÷ 180 is $0.33 per click.

Turn views into leads: ask for a comment in the video, and send your link by DM to everyone who comments your keyword on Instagram or a Facebook Page. [How comment-to-DM works →](https://phersa.com/comment-to-dm)

## CPM Calculator questions

### What does CPM stand for?

Cost per mille. Mille is Latin for thousand, so CPM is the cost of 1,000 impressions.

### How do I calculate CPM?

Divide the ad cost by the impressions, then multiply by 1,000. $60 for 15,000 impressions is a $4 CPM.

### Is CPM the cost to reach 1,000 people?

No. It is the cost of 1,000 impressions, and one person can see an ad more than once. The cost to reach 1,000 accounts is a separate number. Add your reach to see it.

### What is the difference between CPM and CPC?

CPM is what you pay for 1,000 impressions. CPC is what you pay, on average, for one click. Both come from the same spend, and CTR links them: CPC = CPM ÷ (10 × CTR in %). A $4 CPM at a 1.2% CTR is $4 ÷ 12 = $0.33 a click.

### What is a good CPM on Instagram or Facebook?

There is no fixed good number. CPM changes with who you target, where the ad shows and how many other advertisers want the same people. Compare it with your own past campaigns, and judge an ad by what it brings in, not by CPM alone.

[Work out your ROAS →](https://phersa.com/tools/roas-calculator)

### How many impressions will my budget buy?

Budget ÷ CPM × 1,000. Pick Impressions, then type your budget and a CPM from a past campaign. Treat the answer as a rough guide: the real CPM moves once the ad runs.

## More free tools

- [ROAS Calculator — Return on ad spend from revenue and ad spend, the profit left after ads, and the revenue a target ROAS needs.](https://phersa.com/tools/roas-calculator)
- [Cost Per Lead Calculator — Cost per lead from ad spend and leads, and the most a lead is worth from your close rate, price and margin.](https://phersa.com/tools/cost-per-lead-calculator)
- [Instagram Engagement Rate Calculator — Engagement rate for any Instagram or Facebook post, by followers and by views.](https://phersa.com/tools/instagram-engagement-rate-calculator)

[See all free tools for AI persona creators →](https://phersa.com/tools)

Source: https://phersa.com/tools/cpm-calculator