How ConversionBench computes percentiles
Every benchmark on ConversionBench is one of three things: a verified reading from a primary source, a derived interpolation that says so on the page, or research-pending that 404s rather than fabricates a number. This page documents the rules. Who applies them is a separate page.
1. Source selection
Each metric anchors to a primary source. The shortlist: Baymard Institute, WordStream, Adobe Digital Insights, Mixpanel, Contentsquare, Littledata, HubSpot, and VWO.
Each source gets a credibility score from 1 to 10 based on three things: sample size (a 487-site Baymard panel scores higher than a 50-customer competitor blog), methodology transparency (the report shows the formula and excludes outliers), and recency (a 2024 reading scores higher than a 2019 one). Sources scoring 6 or below are not cited as primary.
2. Row state
Every benchmark row in our dataset is in exactly one of three states:
- Verified — a direct reading from a credibility-7+ primary source. Cited inline. Fully indexable. The 25/50/75 numbers come from the source verbatim or with disclosed adjustment.
- Derived— interpolated from the primary source plus adjacent verticals. Disclosed on the page with a “derivation notes” section. Used when a source publishes a category average but not a per-vertical breakdown we’re confident reproducing.
- Research pending — no credibility-7+ source yet. The page returns 404. We never publish a placeholder number to fill the matrix.
3. Percentile interpolation
The calculator uses piecewise linear interpolation between p25, p50, and p75 anchor points, with diminishing returns above the 75th. For lower-is-better metrics (cart abandonment, churn, bounce rate), the curve flips so that low rates rank highest.
Concretely: if your rate sits between p25 and p50, your percentile is linear on that segment. Between p50 and p75 it’s linear again. Above p75 the slope flattens — an industry top performer doesn’t get rewarded with unbounded ranking for being twice the median. The calculator runs the whole computation in your browser — nothing you type is sent to a server.
4. Refresh cadence
Source data refreshes once per year, anchored to when primary publishers ship their annual reports (typically March-May for the prior calendar year). Every benchmark page shows both the source-data year (when the underlying study published) and a last verified stamp (when ConversionBench last re-checked the row against the source).
Currently anchored to: source data 2024 · last verified .
5. What we don’t do
- No fabricated numbers. The matrix has gaps. We show them as gaps.
- No competitor-blog citations. Other people’s benchmark roundups are not primary sources, even when they’re well-written.
- No paid placement in the data. Sources are cited because their data is good — nobody can pay to be cited, to change a number, or to move a percentile. Where a page carries a commercial link it is labelled and separated from the benchmark, per our affiliate disclosure.
- No newsletter, no email capture, no popups, no “subscribe to get the methodology”. The methodology is this page.
Primary sources
Full source list with credibility scores at /source.
Spot a problem?
If a benchmark looks wrong, a source has been superseded, or a derivation should be reconsidered, email hello@caslonmedia.com. Methodology corrections are append-only — we log what changed and why.