Bowling Score Calculator
Calculate a ten-pin bowling score from the pins knocked down on each ball, with strikes and handicap.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Ten-pin scoring is cumulative: a strike adds ten plus the next two balls and a spare adds ten plus the next ball, which is why a perfect game is 300 rather than 120. Enter the pins from each ball in order — a strike is simply 10.
Worked example
calculated with the default values below
Pins knocked down on each ball 10, 7, 3, 9, 0, 10, 10, 8, 2, 9, 1, 10, 10, 10 · Entering average 165 · Handicap basis 200 Total score 195 · Frames completed 10 · Strikes 6 · Spares 3 · Pins per frame 19.5 · Handicap 28 · Note Partial game: 10 frames entered; final or bonus rolls may be pending
General background references
Disclaimer
These calculators give general mathematical results. They suit study, planning and estimation — verify anything that feeds a graded submission, a published figure or a financial commitment.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
f_j = { 10+b₁+b₂, a_j=10; 10+b₁, a_j≠10 ∧ a_j+c_j=10; a_j+c_j, a_j+c_j<10 }; total = Σ_{j=1}^{10} f_j
- a_j
- First-ball pins in frame j
- c_j
- Second-ball pins in frame j
- b₁
- Pins on the next ball
- b₂
- Pins two balls later
- f_j
- Frame j score
- total
- Total pinfall
Frames are walked in order: a strike consumes one ball and adds the next two balls, a spare consumes two and adds the next ball; iteration stops after 10 frames or when the input ends; handicap = max(0, round((basis−average)·0.8)).
Frequently asked questions
How does the calculator score a partial game?
It applies ten-pin scoring: a strike earns 10 plus the next two rolls, and a spare earns 10 plus the next roll. A game with fewer than ten frames is marked partial; a bonus roll that has not happened yet is not known, so its displayed total can change. Rolls must be whole numbers from 0 to 10, and a non-strike frame cannot exceed 10 pins.