Tools - SemFirula

Running pace calculator

Find your pace per kilometer and per mile from any distance and time, and see the predicted time for 5 km, 10 km, half marathon and marathon.

One rep max calculator

Estimate your one rep max from a set taken to failure, see how much the formulas disagree, and get the load for every rep range.

Penalty shootout simulator

Mark each kick and see exactly when the shootout was decided, how many kicks no longer mattered and how many each side still has.

Football points percentage calculator

Work out the points percentage from wins, draws and defeats, and see the highest and lowest it can still finish at with the matches that are left.

Heart rate zones and VO2 max calculator

Work out your training zones from your age and resting pulse, see how much the choice of formula and of method actually changes them, and get a rough VO2 max.

Football cup bracket generator

Build a knockout bracket for 2 to 64 teams with the usual seeding and byes for the best, and save it as an image drawn on your own device.

Body mass index and body composition

Work out the body mass index, estimate body fat from a tape measure, and see why the two disagree so often on an athletic body.

Football fixture generator: the round robin schedule

Build a round robin schedule for any number of teams or groups, with the home and away sides balanced instead of left to the rotation.

Football tactical board

Lay out a formation on a football pitch, drag the players where you want them, and take them off by pulling them past the touchline.

Football league table and tiebreakers

Paste the results, get the table, and see how the champion changes when the tiebreaker is goal difference instead of the matches between the tied teams.

Football: which youth age group a player falls into

Work out the age group from a date of birth, and see how much of a head start the calendar hands to whoever was born just after the cutoff.

Training load progression calculator

See how many weeks a fixed increment per session lasts before it reaches the ceiling you name, where it would land in a year, and why the same jump stops being felt.

Football possession time and tempo calculator

Turn a possession percentage into minutes with the ball, see how small a share of the running clock that really is, and measure tempo per minute of possession instead of per minute of match.

Football shot angle: how much goal you can see

Put a point on the pitch and get the exact slice of goal a shot from there can aim at, why being closer often means seeing less, and whether going square beats going forward.

Sport unit converter, and the names that mean two different things

Convert distance, weight and speed between the metric and imperial systems, and see the milestones that carry the same name on both sides while being measurably different.

Can you still catch them, and where a points gap stops being reversible

Compare your points and matches left with a rival's and see whether the gap can still be closed, including the case where winning every match you have left is not enough.