Success per die
Mistake: Entering 0.5 when you mean 50%.
Fix: Enter 50 for 50%; 0.5 represents 0.5%.
Calculators · Free
Fixed-hit combat expectation
Estimate attack counts for a tabletop damage model.
01Enter your values
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02Fixed-hit combat expectation
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How it works
Estimate attack counts for a tabletop damage model.
h=ceil(HP/damage); E[attacks]=h/p; E[misses]=h(1−p)/p
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Discovery source
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Inputs are processed on this page and are never sent to a server.
About this tool
Use tool ↑Estimate attack counts for a tabletop damage model.
Round health divided by fixed damage upward to get required hits. Divide hits by success probability for expected attacks; subtract hits for expected misses.
How to use it
- Enter your values
Target health · Fixed damage per hit · Success per die
- Calculate / generate
Estimate attack counts for a tabletop damage model.
- Result
Expected attacks: 6 Hits required: 3 Expected misses: 3
Calculation method
- Round health divided by fixed damage upward to get required hits.
- Divide hits by success probability for expected attacks; subtract hits for expected misses.
h=ceil(HP/damage); E[attacks]=h/p; E[misses]=h(1−p)/p
Fixed-hit combat expectation
- Target health
- 25
- Fixed damage per hit
- 10
- Success per die
- 50 %
Result
Expected attacks: 6 Hits required: 3 Expected misses: 3
Frequently asked questions
Limits and key assumptions
Not a win percentage or guaranteed number of turns. No critical hits, variable damage, healing or changing hit chance. Supply the final hit chance, not an armor-class score.
Where does my data go?
Calculations run on your device. Form inputs are not sent to a server.
Terms and definitions
Enter your values
- Target health
Round health divided by fixed damage upward to get required hits.
Enter a numerical value for this quantity.
Minimum: 0.000001 · Maximum: 1000000000
- Fixed damage per hit
Round health divided by fixed damage upward to get required hits.
Enter a numerical value for this quantity.
Minimum: 0.000001 · Maximum: 1000000000
- Success per die
Divide hits by success probability for expected attacks; subtract hits for expected misses.
Enter a percentage, not its decimal fraction: 50 means 50%. Use the unit shown beside this field. %
Minimum: 0.000001 · Maximum: 100 %
Result
- Result
Round health divided by fixed damage upward to get required hits. Divide hits by success probability for expected attacks; subtract hits for expected misses.
Calculated from your entries using the method below.
- Expected attacks
Divide hits by success probability for expected attacks; subtract hits for expected misses.
Calculated from your entries using the method below.
- Hits required
Round health divided by fixed damage upward to get required hits.
Calculated from your entries using the method below.
- Expected misses
Divide hits by success probability for expected attacks; subtract hits for expected misses.
Calculated from your entries using the method below.
- Value
Round health divided by fixed damage upward to get required hits. Divide hits by success probability for expected attacks; subtract hits for expected misses.
Calculated from your entries using the method below.
- Unit
Round health divided by fixed damage upward to get required hits. Divide hits by success probability for expected attacks; subtract hits for expected misses.
Calculated from your entries using the method below.
Common mistakes and quick fixes
Limits and key assumptions
Mistake: Treating a result as valid outside the described scope.
Fix: Not a win percentage or guaranteed number of turns. No critical hits, variable damage, healing or changing hit chance. Supply the final hit chance, not an armor-class score.
Limits and key assumptions
- Not a win percentage or guaranteed number of turns. No critical hits, variable damage, healing or changing hit chance. Supply the final hit chance, not an armor-class score.
- Displayed results may be rounded; rounding does not add measurement precision.