Plain-language answer
What does this cold email reply-rate number actually mean, and is it supported by dated evidence?
The Denominator Decoder re-expresses a reply-rate claim on a stated denominator and checks it against dated benchmark bands, using one versioned claims dataset that also generates the checker and the Claims Index.
Short answer
Use evidence that can survive a second reader.
- A reply rate is read as a fraction; the stated denominator, not the percentage, decides whether a comparison is honest.
- A total-sent or delivered denominator is placed on the same axis as the sourced benchmark bands; an opens or unique-opener denominator is refused, not converted, because Apple Mail Privacy Protection makes the conversion unverifiable.
- A number with no stated denominator returns the question to ask, treated as a first-class result rather than a failure.
- Every verdict and benchmark is a human-reviewed record with a primary source and date; material vendor disclosures trigger review and the active dataset receives a full review at least quarterly.
Worked example
See the decision in a fictional case.
- Id
- reply-rate-single-number
- Claim Text
- The cold email reply rate is X%.
- Verdict
- MYTH
- Real Finding
- There is no single verified figure. Belkins measured 0.45% replies per total send across 7,530,489 emails in 2025. Instantly measured 3.43% per send the same year. Different denominators, different populations, both real.
- Do Instead
- Ask what the number is divided by before you repeat it. Report your own reply rate as replies over total sends, with the sample size and date range next to it.
- Category
- reply-rate-math
Use Denominator DecoderInspect the full methodTake it into the matching Petrichor work
What this answer cannot establish
- The decoder normalizes and compares stated numbers; it does not verify the sender's underlying data or predict campaign performance.
- Benchmark bands describe the populations their sources measured, which are not always B2B sales.