Basic formulas for digital media planning

Planning makes happy people.

Introduction

Media planning, or campaign planning in general, requires you to set goal metrics, so that you are able to communicate the expected results to a client. In digital marketing, these are metrics like clicks, impressions, costs, etc. The actual planning process usually involves using estimates — that is, sophisticated guesses of some sorts. These estimates may be based on your previous experience, planned goal targets (when for example given a specific business goal, like sales increase), or industry averages (if those are known).

Calculating online media plan metrics

By knowing or estimating some goal metrics, you are able to calculate others. But sometimes it’s hard to remember the formulas. This is a handy list to remind you of the key formulas.

  • ctr = clicks / imp
  • clicks = imp * ctr
  • imp = clicks / ctr
  • cpm = cost / (imp / 1000)
  • cost = cpm * (imp / 1000)
  • cpa = cpc / cvr
  • cpa = cost / conversions
  • cost = cpa * conversions
  • conversions = cost / cpa

In general, metrics relating to impressions are used as proxies for awareness and brand related goals. Metrics relating to clicks reflect engagement, while conversions indicate behavior. Oftentimes, I estimate CTR, CVR and CPC because 1) it’s good to set a starting goal for these metrics, and 2) they exhibit some regularity (e.g., ecommerce conversion rate tends to fall between 1-2%).

Conclusion

You don’t have to know everything to devise a sound digital media plan. A few goal metrics are enough to calculate all the necessary metrics. The more realistic your estimates are, the better. Worry not, accuracy will get better in time. In the beginning, it is best to start with moderate estimates you feel comfortable in achieving, or even outperforming. It’s always better to under-promise than under-perform. Finally, the achieved metric values differ by channel — sometimes a lot — so take that into consideration when crafting your media plan.