What is CTR?

CTR — click-through rate — is the share of ad deliveries that got a click: clicks divided by impressions, shown as a percentage. It measures whether the ad earns a response from the people who see it, before any question of what happens on your site.

Formula

CTR = clicks ÷ impressions × 100

Worked example

Channel A: 3,000 clicks on 100,000 impressions — 3.0%. Channel B: 2,000 clicks on 400,000 impressions — 0.5%. The blended CTR is not the average of 3.0 and 0.5 but 5,000 ÷ 500,000 = 1.0%, pulled toward B because B serves four times the volume. That weighting is deliberate: a rate metric always reflects where the impressions actually went.

How Saldo Metrics computes it

Every CTR figure divides summed clicks by summed impressions from the same rows — never an average of pre-computed rates:

• blendedCtr (the Overview KPI) is computed from the period's total clicks and total impressions across all channels.
• v_channel_performance and v_campaign_performance carry ctr_pct at channel and campaign grain; the channel summary and campaign table re-aggregate the daily rows across the selected period the same way.
• v_format_performance repeats the division per ad format on the Creatives tab.
• The creative fatigue card compares each creative's last-7-day CTR against the prior 7 days (v_creative_fatigue's ctr_recent and ctr_trend_pct) — a falling trend there flags fatigue before the aggregate CTR moves.

Why it matters

CTR is the earliest performance signal you get: it moves within hours of a creative or audience change, while revenue metrics take days to settle. It is also the main input to the fatigue score — a creative whose CTR decays week over week is wearing out its audience regardless of what it did historically.

Common mistakes

• Comparing CTR across channels or formats as if it were one benchmark. Search ads, feed ads and video see structurally different click behaviour; compare a channel against its own history, not against another channel.
• Averaging CTRs instead of recomputing from totals. The average of per-campaign CTRs weights a tiny campaign the same as a huge one and can point the wrong way.
• Chasing CTR without watching conversion rate. Provocative creative can raise clicks while attracting people who never buy; the click was never the goal.

Where you see this in the app

Marketing → Overview, as the Blended CTR KPI, per channel and per campaign; Marketing → Creatives, per format and in the fatigue card's 7-day CTR trend.