The instrument
CPM calculator
By Oliver Wakefield-Smith · updated October 2026
The short answer
One slate, three solves. Enter any two of total spend, impressions and CPM; the third computes live. If you do not know a rate, load a preset: each one is a sourced, dated channel average, never a guess. State lives in the URL, so a solved result is shareable.
your CPM
$8.33
$1,000 across 120,000 impressions is a $8.33 CPM.
The three modes
- Solve CPM. You have a bill and an impression count. Spend ÷ impressions × 1,000. This is the post-campaign audit mode.
- Solve impressions.You have a budget and a rate. Spend ÷ CPM × 1,000. This is the planning mode: at Meta's December 2025 tracker average of $10.02, $1,000 buys about 99,800 impressions.
- Solve budget. You need N impressions at a known rate. CPM × impressions ÷ 1,000. A million impressions at $2.84(TikTok's December 2025 tracker average) costs $2,840.
Where the presets come from
Five presets, two sources, retrieved October 2026. Meta at $10.02 (December 2025) and $8.06 (June 2025), and TikTok at $2.84(December 2025), come from Gupta Media's public tracker table; Meta's figure covers Facebook and Instagram together. Podcast $18 (30s) and $24 (60s) are the low ends of the host-read ranges Libsyn Ads (formerly AdvertiseCast) publishes. Channels with no citable figure (Google Display, LinkedIn, CTV and most of the rest) get no preset, because a preset would be an invention. The full provenance table is in the source ledger.
Sanity-check the output against the rate table, read the formula page for the unit traps, or see the arithmetic applied in five worked scenarios. Verdict logic lives at is my CPM good?