Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Donor retention rate
45.0%
Donor lifetime value
$300
Annual revenue lost to lapse
$127,204
Cost to replace lapsed donors
$73,150
LTV at improved retention
$330
Portfolio value created by the improvement
$42,051
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter donors last year.
- 2Enter of those, gave again this year.
- 3Enter average gift ($).
- 4Enter gifts per donor per year.
- 5Enter cost to acquire a new donor ($).
- 6Enter retention improvement to model (pts).
- 7Read your donor retention rate on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
The average nonprofit loses roughly half its donors every year, and replacing them costs several times more than keeping them. This calculates your retention rate, the revenue leaking out the bottom, and what a small retention improvement is worth.
Worked example
Using the values the calculator loads with:
Inputs
- Donors last year: 1400
- Of those, gave again this year: 630
- Average gift: 118 $
- Gifts per donor per year: 1.4
- Cost to acquire a new donor: 95 $
- Retention improvement to model: 5 pts
Results
- Donor retention rate: 45.0%
- Donor lifetime value: $300
- Annual revenue lost to lapse: $127,204
- Cost to replace lapsed donors: $73,150
- LTV at improved retention: $330
- Portfolio value created by the improvement: $42,051
What each field means
Inputs
- Donors last year
- The donors last year used in the calculation. Starts at 1400 so you have a working example on load.
- Of those, gave again this year
- The of those, gave again this year used in the calculation. Starts at 630 so you have a working example on load.
- Average gift ($)
- The average gift used in the calculation, measured in $. Starts at 118 $ so you have a working example on load.
- Gifts per donor per year
- The gifts per donor per year used in the calculation. Starts at 1.4 so you have a working example on load.
- Cost to acquire a new donor ($)
- The cost to acquire a new donor used in the calculation, measured in $. Starts at 95 $ so you have a working example on load.
- Retention improvement to model (pts)
- The retention improvement to model used in the calculation, measured in pts. Starts at 5 pts so you have a working example on load. Accepted range: 0–40 pts.
Results
- Donor retention rate
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Donor lifetime value
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Annual revenue lost to lapse
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cost to replace lapsed donors
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- LTV at improved retention
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Portfolio value created by the improvement
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What is a good retention rate?
Sector-wide it hovers near 45%. First-time donor retention is much worse at roughly 20%, while multi-year donors retain above 60%, so segment before you judge your number.
What actually moves retention?
A thank-you within 48 hours, a report showing what the last gift did, and a second ask that references the first gift. Prompt acknowledgment alone measurably lifts second-gift rates.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Donor Retention Rate Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/donor-retention
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/donor-retention" target="_blank" rel="noopener">Donor Retention Rate Calculator — RevenueLab</a> (2026).</p>
Source: [Donor Retention Rate Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/donor-retention) (2026).