The Beginner’s Guide to Outdoor Auditing

19/03/2021 4:05 PM

By 23 Media Audits

Outdoor Audit Guide

Outdoor or ‘Out of Home’ (OOH) advertising can be a potent tool for showcasing your messaging to a wide range of potential consumers on a big stage, but do you know how to measure its effectiveness? Are you unclear on what an outdoor audit involves, or what process is used to identify its performance? If so, let us take you through some of the basics.

Outdoor Audit Guide

What is Outdoor Auditing?

An OOH audit involves the measurement of campaign performance against a set of industry benchmarks. This will provide insight into the success of a campaign by measuring both the number of people who have seen it and its overall impact.

Outdoor Audit Dashboard
Over the past 3 years of working with 23 Media Audits we have focused on our outdoor efficiencies as a key priority to deliver similar KPI’s like our TV and digital outputs. We have not only made monetary savings but aligned our price, quality and targeting for outdoor behind a unified set of KPI’s.
Client – Retail

What does an OOH Audit Involve?

An OOH audit involves a detailed analysis of the key components of your campaign in order to build up a picture of performance. These key components include verification of sites / digital placements, competitor analysis, audience profiling & conversions, opportunities to see’ by campaign, visual attention vs. Market & category averages, cost performance by site and audit recommendations & action points.

Outdoor Audit Dashboard Parameters

Using data-driven metrics allows advertisers to build up a detailed picture of how many and how often ads are seen and helps pinpoint what type of people are viewing the campaigns. This enables advertisers to measure campaign success based on solid data and develop effective outdoor advertising strategies in the future.

For a quick overview download our 10 Step Guide For Outdoor Media Plans which contains key measurement criteria for successful outdoor advertising campaigns.

Did you know?

OOH accounts for 5.2% of total advertising spend in the UK but can rise to over 8% of spend for advertisers classed as small-medium in size. 23 Media Audits work with many of these challenger brands and regional advertisers, giving us the expertise necessary to identify the best OOH strategy for your business.

What Parameters Does an Outdoor Audit Cover?

KPI Setting

Setting clear KPI’s is an essential element of ensuring an effective outdoor campaign and audit process. Below you will find some examples of our key measurements for success.


This is simply the number of unique individuals who see an advert. A good top-line indicator for campaigns focused on messaging with a broad appeal.


This delves a little deeper than Reach and is a measure of how many times an advert is actually seen by people (i.e. one individual could view an advert a number of times over its lifecycle).


This measure is calculated by dividing the Reach number into the Impacts to provide a ‘frequency’ for a certain period of time. This can be compared to previous campaigns and wider industry benchmarks to monitor relative campaign effectiveness.


A percentage figure that indicates the proportion of a desired target group of people who have seen the campaign within its lifecycle. This is a useful measurement for campaigns targeted at a specific age or demographic profile.


Perhaps the most important KPI is measuring people’s actual interaction with the advert either through internal metrics such as monitoring sales ‘before and after’, ad specific URLs or QR codes, campaign hashtags or website survey data capture or interrogating the length of the creative against the message type and reach levels.

Did you know?

Advertisers who invest 15% of their ad budget in OOH realize a profit growth of 20% on average compared to advertisers who do not invest in outdoor campaigns.

What Can Our OOH Audit Deliver?

Outdoor auditing in 2019 & 2020 has saved our clients in the region of 20% on their advertising spend. That equates to a saving of £200 for every £1000 spent pre-audit on the same campaign, meaning only £800 needs to be spent to reach the same amount of people.


An affordable price for brands with a X10 saving vs. the audit fee.


Our Outdoor Audit has the ability to generate savings of 20%+ vs. an unaudited delivery.


A quick process from data collection through to presentation of results.


A human insight into the deliverables – the design is bespoke to individual campaign KPI’s.


Makes your media buying more efficient and makes your marketing output more effective.

For further insight Download Our Outdoor Audit Guide which contains a more in depth look at all outdoor auditing parameters and includes example charts and dashboards.