Minesweeper 3BV Calculator
Work out the 3BV of any Minesweeper board — the minimum number of left-clicks needed to clear it with
perfect play. Generate a standard board, or paste your own layout using * for a mine and
. for a safe cell. Everything runs in your browser; nothing is uploaded.
An opening is a connected region of zero-adjacency cells. Clicking anywhere in it clears the whole region plus its bordering numbers in one click, which is why openings dominate 3BV.
3BV/s and efficiency
Enter your finishing time and click count to convert a 3BV figure into the two metrics that actually get compared.
How 3BV is calculated
3BV stands for Bechtel's Board Benchmark Value. It counts the fewest left-clicks a perfect player would need, and it is computed in two parts:
- Find every opening — a connected group of cells with zero adjacent mines. Each opening counts as one click, no matter how large it is, because a single click cascades through the whole region and reveals its bordering numbers too.
- Every remaining safe cell that is not touched by an opening counts as one click of its own.
Add the two together and you have the board's 3BV. A board with generous openings can have a much lower 3BV than a board of the same size where the mines are spread evenly — which is exactly why record chasers restart until they get a low-3BV, high-opening layout.
Why 3BV/s beats raw time
Raw time says nothing about how hard the board was. A 60-second Expert clear on a 120 3BV board and a 60-second clear on a 200 3BV board are very different performances. Dividing 3BV by your time normalises for board difficulty, which is why competitive players compare 3BV/s rather than seconds. There is more on this in the 3BV explainer and the efficiency guide.
Where efficiency fits
Efficiency compares your click count against the theoretical minimum: 3BV divided by clicks used. Exactly 3BV clicks is 100%. Because a chord can resolve several cells in one action, skilled players routinely finish above 100%. Learn the technique in the chording explainer.
Minesweeper 3BV FAQ
What is 3BV in Minesweeper?
3BV is the minimum number of left-clicks needed to clear a board with perfect play. Every opening (a connected region of zero cells) counts as one click, and every remaining safe cell that is not part of an opening counts as one more.
How do you calculate 3BV/s?
Divide the board's 3BV by your finishing time in seconds. A 150 3BV Expert board cleared in 75 seconds is 2.0 3BV/s.
What is Minesweeper efficiency?
Efficiency is 3BV divided by the number of clicks you actually used, as a percentage. Using exactly 3BV clicks is 100%. Chording can push efficiency above 100% because one chord can do the work of several clicks.
Ready to put it into practice? Play an Expert board, check the Expert leaderboard, or see how good your time is.