--- title: "What is frequency capping? | AdBuyMCP" description: "Limiting how many times one person or household sees the same advert within a given period, to control wear-out and wasted impressions." url: "https://adbuymcp.com/glossary/frequency-capping" --- [Home](https://adbuymcp.com/) / [Glossary](https://adbuymcp.com/glossary) / Frequency capping Targeting and identity # What is frequency capping? Limiting how many times one person or household sees the same advert within a given period, to control wear-out and wasted impressions. It is set per campaign, per channel or, rarely, across channels, and that granularity is what decides whether the cap means anything. Also called frequency cap [Get my plan and price](https://adbuymcp.com/start) [Book a 30-minute call with the founder](https://adbuymcp.com/contact#book) Free, with no card. We read your homepage, draft who buys from you and show your monthly price before you join the waitlist. Nothing is bought until you've approved the plan and the ads. What it means here ## Here is what the term means for a UK buyer The definition above holds anywhere. Buying media in the UK adds the detail below, including where AdBuyMCP does something different. Almost every platform caps within itself and almost none caps across sellers, which is why a multi-channel plan quietly overexposes the same households. Capping across channels requires one exposure record keyed on something every channel can supply. AdBuyMCP's exposure ledger is built for exactly that, on four keys of decreasing precision. The ledger is built, and labelled sample data is its only source today. A live report proves aggregate delivery, and household exposure needs a key with consent behind it, so AdBuyMCP does not create identities from a report. That is why an AdBuyMCP awareness plan states its 3, 5 or 12 times a week as planned frequency. ## Why does a per-platform cap fail across channels? Each platform caps within its own inventory and cannot see the others. A plan on four channels with a cap of four on each allows up to sixteen exposures for a household that appears on all of them. The combined reach in a report is inflated by the same overlap, because adding each channel's reach counts those households once per channel. Launches suffer most, because a launch buys the same people repeatedly across channels by design. ## What does cross-channel capping need? It needs one exposure record that every channel writes into, keyed on something all of them can supply. AdBuyMCP's ledger uses four keys: an opaque household key, a hashed advertising id, a consent-based id, and a postcode sector, which is the coarsest and always available. Cinema and DOOH usually land on the postcode sector. Hashed advertising ids are held for at most 90 days and then stripped from the event, which re-grades it to a coarser key and keeps the record. Resolution between key spaces happens in one module only, the key-translation service. Read next - [Why cross-channel frequency capping rarely happens Goes deeper](https://adbuymcp.com/guides/frequency-capping-across-channels) - [The four channels in an awareness plan Channels](https://adbuymcp.com/channels) - [What UK awareness advertising costs Cost](https://adbuymcp.com/cost) - [What a fidelity score measures Guide](https://adbuymcp.com/guides/what-a-fidelity-score-is) Type your company website or work email to see who we think buys from you and what reaching them 3, 5 or 12 times a week would cost. [Get my plan and price](https://adbuymcp.com/start) Free, with no card. Related terms ## These terms sit next to this one Most confusion in media buying comes from two adjacent terms being used interchangeably, so these are the neighbours worth reading next. - ### [Frequency](https://adbuymcp.com/glossary/frequency) The average number of times the people in an audience see an advert in a period, usually a week or a whole campaign. It is impressions divided by the people reached, so it describes the audience on average and says nothing certain about any one person. - ### [Deduplication](https://adbuymcp.com/glossary#deduplication) Removing the double-counting that occurs when the same person is reached by more than one channel or placement in a campaign, so that combined reach reflects distinct people rather than the sum of each channel's separate count. - ### [Reach](https://adbuymcp.com/glossary#reach) The number of distinct people or households exposed to a campaign at least once, as opposed to the total number of impressions delivered. Usually expressed as a count or as a percentage of a defined universe. - ### [Exposure ledger](https://adbuymcp.com/glossary/exposure-ledger) A single record of advertising exposures across every channel, keyed on whichever of four identifiers a channel can supply, with per-key legal grading. They are an opaque household key, a hashed advertising id, a consent-based id and a postcode sector. Same group ## These terms are also in Targeting and identity How an audience is described to a seller, and how much of the description survives. Most media-buying problems start at this translation step. - [Audience segment](https://adbuymcp.com/glossary/audience-segment) - [First-party data](https://adbuymcp.com/glossary/first-party-data) - [Third-party data](https://adbuymcp.com/glossary#third-party-data) - [Contextual targeting](https://adbuymcp.com/glossary#contextual-targeting) - [Lookalike audience](https://adbuymcp.com/glossary#lookalike-audience) - [Retargeting](https://adbuymcp.com/glossary#retargeting) - [Experian Mosaic](https://adbuymcp.com/glossary#experian-mosaic) - [CACI Acorn](https://adbuymcp.com/glossary#caci-acorn) [All 81 terms](https://adbuymcp.com/glossary)