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    CPM calculator: convert CPM, CPC, CPA and vCPM with viewability rate and IVT adjustments

    Published · Last updated
    Next scheduled review:

    By Art Kukharenko, CEO

    This CPM calculator turns spend and counts into CPM, CPC, CPA and vCPM, then shows what you pay for impressions that were valid and viewable. It applies the Media Rating Council's viewability rate and measured rate definitions and removes invalid traffic first. You can also convert one price model into another. Nothing leaves your browser.

    CPM calculator

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    • Billed · 1000000 impressions
    • Valid · 1000000 impressions
    • Measured · 1000000 impressions
    CPM
    5.00 USD
    Show the math

    Cost ÷ billed impressions × 1,000 · Cost 5000 · Billed 1000000

    CPC
    n/a
    Show the math

    Cost ÷ clicks · Cost 5000 · Billed 1000000

    CPA
    n/a
    Show the math

    Cost ÷ conversions · Cost 5000 · Billed 1000000

    IVT-adjusted CPM
    5.00 USD
    Show the math

    Cost ÷ valid impressions × 1,000 · Cost 5000 · Billed 1000000

    vCPM
    n/a
    Show the math

    Cost ÷ viewable impressions × 1,000 · Cost 5000 · Billed 1000000

    Strict vCPM
    n/a
    Show the math

    Cost ÷ (measured impressions × viewable rate) × 1,000 · Cost 5000 · Billed 1000000

    Projected vCPM
    n/a
    Show the math

    Cost ÷ (valid impressions × viewable rate) × 1,000 · Cost 5000 · Billed 1000000

    CTR
    0.00%
    Show the math

    Clicks ÷ billed impressions × 100 · Cost 5000 · Billed 1000000

    CVR
    n/a
    Show the math

    Conversions ÷ clicks × 100 · Cost 5000 · Billed 1000000

    Viewable share of billed impressions
    n/a
    Show the math

    Viewable ÷ billed impressions × 100 · Cost 5000 · Billed 1000000

    Billed impressions
    1000000
    Valid impressions
    1000000
    Measured impressions
    1000000
    Viewable impressions
    n/a

    Contents

    Key facts

    • A viewable display impression needs half its pixels for one second. The MRC counts a display ad as viewable when at least 50% of its pixels are in view for one continuous second. Video needs two continuous seconds, and display ads of 242,500 pixels or more need 30% (MRC Viewable Ad Impression Guidelines, Version 2.0, 18 August 2015).
    • Viewability rate leaves out what nobody measured. In the MRC's own example, 300 viewable, 200 non-viewable and 500 unmeasured impressions give a 60% viewable rate, a 50% measured rate and only 30% viewable impressions in the distribution (MRC, 2015, page 13).
    • Paying by vCPM means paying only for viewable impressions. Google Ads describes viewable CPM as bidding on 1,000 viewable impressions and paying for those measured as viewable (Google Ads Help, accessed 9 November 2026).
    • Typical viewability differs by format. IAS reported global display viewability of 67.9% and video viewability of 79.7% in its 21st Media Quality Report (company data) (IAS, 9 July 2026).
    • Cheap CPMs can cost more per quality impression. In the ANA's Q2 2026 benchmark, lower performers paid a $6.55 CPM but a $13.80 TrueCPM; higher performers paid $7.90 and $11.94 (Fiducia on the ANA benchmark, 6 August 2026).
    Jump to the table

    How to use the CPM calculator

    1. Pick a mode. "Campaign totals" works from an invoice or a report. "Convert a price" turns a CPM, CPC, CPA or vCPM quote into the other models. "Quality gap" compares a CPM with the price per quality impression.
    2. Enter spend and counts. Use billed impressions, clicks and conversions from the same report and date range. The currency only changes labels.
    3. Add invalid traffic. Enter the share of impressions your verification vendor filtered as general or sophisticated invalid traffic.
    4. Add viewability. Enter the measured rate and the viewable rate exactly as your vendor reports them. Then choose how to treat impressions nobody measured.
    5. Read and share. The results panel shows every price, the formula behind it and the count it divides by. Copy a link that holds your inputs, or download a CSV.

    Formulas and definitions behind each number

    Each price is cost divided by a count. The only question is which count. A CPM divides by billed impressions, a CPC by clicks and a CPA by conversions or other agreed actions. A vCPM divides by viewable impressions, and the calculator removes invalid traffic before it counts any of them.

    CPM            = cost / impressions × 1,000
CPC            = cost / clicks
CPA            = cost / actions
CTR            = clicks / impressions
CVR            = actions / clicks
valid          = impressions × (1 − IVT rate)
IVT-adjusted CPM = cost / valid × 1,000
measured       = valid × measured rate
viewable       = measured × viewable rate        (strict: unmeasured never counts)
viewable       = valid × viewable rate           (projected: unmeasured view at the same rate)
vCPM           = cost / viewable × 1,000
eCPM from CPC  = CPC × CTR × 1,000
eCPM from CPA  = CPA × CTR × CVR × 1,000
eCPM from vCPM = vCPM × (1 − IVT rate) × measured rate × viewable rate

    The order matters. The MRC says a viewable impression must first meet the rules for a served impression, including filtering for non-human activity (MRC, 2015). So the calculator applies the IVT rate before it applies any viewability rate.

    The two IVT categories come from the MRC's standard. General invalid traffic (GIVT) is caught by lists and routine checks, such as known data-center traffic and declared crawlers. Sophisticated invalid traffic (SIVT) needs advanced analysis to detect (MRC IVT Standards Addendum, June 2020 update). The calculator takes one combined rate, because invoices rarely split them. The vendors that report these rates are compared in ad fraud detection tools.

    Strict and projected vCPM: why unmeasured impressions change the price

    Viewability vendors cannot measure every impression. The MRC defines the viewable rate over measured impressions only, and it warns against calling the share of all impressions a viewable rate (MRC, 2015). That leaves a choice for anyone pricing by vCPM.

    The strict method counts only impressions that were measured and found viewable. That matches what a seller can prove, and it matches how Google Ads bills viewable CPM, since you pay for impressions "measured as viewable" (Google Ads Help). The projected method assumes unmeasured impressions were viewable at the same rate. It suits planning, when you want an estimate of reach rather than a figure to invoice.

    Take the MRC's example with a $10 cost. The CPM is $10.00. Strict vCPM is $33.33, because only 300 impressions count. Projected vCPM is $16.67, because the 500 unmeasured impressions add 300 more at the 60% rate. Ask which method your seller uses before you compare two vCPM quotes.

    Worked example: a $12,500 display buy

    A buyer pays $12,500 for 2,500,000 display impressions. The verification report filters 2% as invalid, measures 90% of the rest and finds 67.9% of those viewable. That is IAS's published global display average, used here as an illustration (IAS, 9 July 2026).

    5 of 5 rows

    Columns (3)

    Billed impressions

    2,500,000

    CPM $5.00

    Valid after 2% IVT

    2,450,000

    IVT-adjusted CPM $5.10

    Measured (90%)

    2,205,000

    n/a

    Viewable (67.9% of measured, strict)

    1,497,195

    vCPM $8.35

    Viewable as a share of billed

    59.89%

    n/a

    Billed impressions

    Count

    2,500,000

    Price

    CPM $5.00

    Valid after 2% IVT

    Count

    2,450,000

    Price

    IVT-adjusted CPM $5.10

    Measured (90%)

    Count

    2,205,000

    Price

    n/a

    Viewable (67.9% of measured, strict)

    Count

    1,497,195

    Price

    vCPM $8.35

    Viewable as a share of billed

    Count

    59.89%

    Price

    n/a

    Download JSON

    Table by AdSovereign, CC BY 4.0.

    The buyer thinks in $5 CPMs but pays $8.35 for each thousand impressions that could be seen. If a second seller quotes an $8.00 vCPM, the second offer is cheaper per viewable impression, even though its CPM looks higher. The same logic sits behind the ANA's TrueCPM, which prices only impressions that are measurable, viewable, fraud-free and not on made-for-advertising sites (Fiducia on the ANA, 6 August 2026).

    The calculator's quality-gap mode reproduces that published gap. Enter the lower performers' $6.55 CPM and $13.80 TrueCPM, and it returns a 47.46% qualifying share and a 52.5% gap at one decimal, the figure the ANA release reports. The higher performers' $7.90 and $11.94 return a 33.8% gap.

    Converting CPM to CPC, CPA and vCPM

    Sellers quote in different models, so a fair comparison needs one unit. The calculator converts every quote to an effective CPM (eCPM) first. It then converts back to the model you want. Two short examples show the arithmetic.

    With illustrative rates, a $0.75 CPC at a 0.35% click-through rate is worth $2.63 per thousand impressions. A $40 CPA at a 0.5% click-through rate and a 2.5% conversion rate is worth $5.00 per thousand. If the CPM offer on the table is $4.00, it wins against the CPA offer and loses against the CPC offer. That holds only if your click and conversion rates hold too; the formulas are the Google Ads definitions applied in reverse.

    Two warnings apply. Conversion rates for a new seller are guesses, so test a range rather than one number. And a CPA with view-through conversions can show more actions than clicks; the calculator then warns rather than refusing. Fees that sit between your budget and the seller, such as DSP and data fees, are a separate question: the ad tech fee calculator handles them, and DSP pricing explained lists published fee structures.

    Methodology and limits

    The formulas follow the MRC's viewable impression guidelines and its IVT standard, and the price models follow the Google Ads definitions linked above. The calculator computes with exact decimals and rounds only for display. Money shows two decimals, or four when the value is under $0.10. Percentages show two decimals. Rounding is half up, so $0.00625 shows as $0.0063.

    It does not judge whether a rate is good. Viewability and IVT rates depend on format, device and supply, and the viewability, attention and brand safety guide covers what drives them. It also does not decide whether a viewable impression is worth buying: attention and outcomes are separate measures. For media that is bought as working media rather than fees, see working media vs non-working media. Retail media buyers who price by return on ad spend can pair this page with the retail media economics calculator. More engineering tools sit in the RTB architecture hub.

    FAQ

    How do you calculate CPM?
    Divide the cost by the number of impressions and multiply by 1,000. A $5,000 campaign that delivers 1,000,000 impressions has a $5.00 CPM. Google Ads describes CPM as paying per one thousand impressions (Google Ads Help, accessed 9 November 2026).
    What is vCPM, and how is it different from CPM?
    vCPM is the cost per thousand viewable impressions. A CPM counts every billed impression; a vCPM counts only those that met the MRC rule of 50% of pixels for one second, or two seconds for video (MRC, 2015). Because fewer impressions count, a vCPM is always equal to or higher than the CPM for the same spend.
    What does viewability rate mean?
    It is viewable impressions divided by measured impressions, viewable plus non-viewable. Impressions nobody could measure are left out (MRC, 2015). Always read it next to the measured rate, which tells you how much of the campaign the figure covers.
    How do I convert CPM to CPC?
    Divide the CPM by 1,000 times the click-through rate. A $4.00 CPM at a 0.10% click-through rate equals a $4.00 effective CPC, using the Google Ads CPC definition of cost per click. The calculator does this in "Convert a price" mode and shows the formula with your numbers.
    Is invalid traffic removed before viewability?
    Yes. The MRC requires a viewable impression to meet the served-impression rules first, including filtering for non-human activity (MRC, 2015). The calculator applies the IVT rate first and the measured and viewable rates after it.
    Why do strict and projected vCPM differ?
    Strict vCPM counts only impressions measured as viewable. Projected vCPM assumes unmeasured impressions were viewable at the same rate. With a 50% measured rate, the strict figure can be twice the projected one, as the MRC's own example shows.

    How this works on owned infrastructure

    The calculator needs four counts that you usually copy from someone else's report: billed impressions, filtered IVT, measured impressions and viewable impressions. When the ad server, the exchange and the verification tag belong to different vendors, those counts come from different logs and rarely match line by line. AdSovereign is an enterprise RTB stack designed to run on infrastructure you control, so impression, IVT and viewability events can land in one event store under your own keys. A vCPM then becomes a query you can rerun and audit rather than a number you take on trust. The architecture page shows where measurement events enter the pipeline, and the TCO calculator compares rented and owned cost lines.

    Sources

    1. Media Rating Council, "MRC Viewable Ad Impression Measurement Guidelines", Version 2.0 (Final with 2015 additions), 18 August 2015. https://mediaratingcouncil.org/sites/default/files/Standards/081815%20Viewable%20Ad%20Impression%20Guideline_v2.0_Final.pdf
    2. Media Rating Council, "Invalid Traffic Detection and Filtration Standards Addendum", June 2020 update (final). https://mediaratingcouncil.org/sites/default/files/Standards/IVT%20Addendum%20Update%20062520.pdf
    3. Google Ads Help, "Bid on viewable impressions using viewable CPM" (accessed 9 November 2026). https://support.google.com/google-ads/answer/3499086?hl=en
    4. Google Ads Help, "Cost-per-thousand impressions (CPM): Definition" (accessed 9 November 2026). https://support.google.com/google-ads/answer/6310?hl=en
    5. Google Ads Help, "Cost-per-click (CPC): Definition" (accessed 9 November 2026). https://support.google.com/google-ads/answer/116495?hl=en
    6. Google Ads Help, "About Target CPA bidding" (accessed 9 November 2026). https://support.google.com/google-ads/answer/6268632?hl=en
    7. Integral Ad Science, "IAS 21st Media Quality Report" press release (9 July 2026). https://integralads.com/news/ias-21st-media-quality-report/
    8. Fiducia, "ANA Programmatic Transparency Benchmark: Q2 2026" (ANA release of 6 August 2026). https://www.fiducia.eco/post/ana-programmatic-transparency-benchmark-q2-2026-working-media-efficiency-reaches-a-record-45
    Changelog
    • 9 November 2026. First edition: three modes, strict and projected vCPM, IVT before viewability, 27 test cases. Next review 9 May 2027.

    Author: Art Kukharenko, CEO, AdSovereign. Published: 10 November 2026. Last updated: 10 November 2026.