Plate calculator: know exactly which plates to load

Doing quick mental math on loaded plates mid-set is a common source of mistakes, and the plate calculator removes it entirely — enter your target weight and which bar you're using, and this barbell plate calculator shows exactly which plates go on each side, both as a number list and a visual stack.

How to use the plate calculator

Choose your unit (kg or lb), enter your target total weight, and select your bar from the dropdown — a standard 20 kg men's Olympic bar, a 15 kg women's Olympic bar, a 10 kg technique bar, or the equivalent pound options (45 lb, 35 lb, 15 lb). The calculator subtracts the bar weight, halves the remainder for one side, and works out the largest plates that fit, down to the smallest fractional plate in your set, showing the result both as a written list ("20 + 10 + 2.5") and a colour-coded visual stack.

Bumper plate colours explained

Competition bumper plates follow a standard colour code by weight in kilograms: red for 25 kg, blue for 20 kg, yellow for 15 kg, green for 10 kg, and white or black for smaller fractional plates, with red again for the small 2.5 kg change plate. This calculator's visual stack uses these same colours, so if your gym uses standard bumper plates, the picture should match what you actually need to grab from the rack without reading a single number.

Choosing the right bar

A standard men's Olympic barbell weighs 20 kg (45 lb); the women's Olympic bar weighs 15 kg (35 lb) and is also slightly thinner, which some lifters with smaller hands prefer regardless of gender. Technique or "training" bars around 10 kg (15 lb) are common for teaching beginners the squat, deadlift or press pattern before adding real load. Pick the bar you're actually using in the calculator — using the wrong bar weight will throw off every plate suggestion that follows.

Limits of the calculator

The result assumes your gym's actual available plates match the standard set built into the calculator (typically 25/20/15/10/5/2.5/1.25 kg or 45/35/25/10/5/2.5 lb) — if your gym has a nonstandard or limited plate selection, you may need to adjust slightly, for example rounding to the nearest weight you can actually load. It also assumes even loading on both sides, which is standard practice and should always be followed for safety and balance.

Using this alongside your training numbers

Pair this tool with the one-rep max calculator: work out a percentage-based target weight for your next set there, then plug that number straight into the plate calculator to see exactly what to load, without doing the subtraction and halving by hand under time pressure between sets. This pairing is especially useful during a percentage-based training block, where your target weight changes slightly from session to session and manual plate math becomes an easy place to make a mistake.

Safety note

Always use collars to secure plates on both ends of the bar, especially at heavier weights, and load and unload the bar evenly from both sides rather than fully loading one side first, which can tip an unracked bar. On heavier lifts, load the largest plates closest to the sleeve's centre stop and smaller plates further out, which keeps the loaded bar balanced and easier to control when unracking, particularly at weights near your working max.

Using the calculator for squat, bench and deadlift

The same calculator works identically whichever compound lift you're loading for — the plate math doesn't change based on the exercise, only the target weight and bar you enter. Many lifters keep this page open across a whole session, updating the target number as they move from a squat working set, to a bench press at a different weight, to a deadlift at a heavier one, rather than recalculating each change by hand.

Privacy

All calculations happen in your browser instantly as you type — nothing is sent to a server, saved to an account, or shared anywhere. Feel free to bookmark the page for quick access before your next session, since there's no login step standing between you and a loaded bar, and the same page works equally well on a phone at the rack or a laptop while planning a session at home.