Plate Calculator
Enter a target weight and the plates you have available, and the calculator tells you what to load on each side of the bar.
Calculate plate loading
Plates per side
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Plates are listed from the bar outwards.
Plates → weight
Tell the calculator what's on the bar and it returns the total, plus every other weight you could build from the same plates.
Total weight
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Weights you can build
Every weight that can be loaded symmetrically with the plates selected.
Plate colours
Colours follow the International Weightlifting Federation (IWF) standard. Not every gym uses colour-coded plates.
How this calculator works
The plate calculator solves a simple problem that is easy to get wrong under a loaded bar: subtract the bar and collars from the total, halve what is left, and build that half from the available plates, largest first.
The calculator does not use a simple greedy algorithm that just adds the largest plate that fits. That approach breaks down when the plate selection is incomplete: 30 kg per side from 25, 20 and 15 kg plates is 15 + 15, but a greedy algorithm would take the 25 first and find no solution at all. Instead the calculator searches every possible combination using dynamic programming and picks the one using the fewest plates. Where no exact match exists, it finds the nearest achievable weight in either direction.
Bear in mind that bars vary between gyms: a men's Olympic bar is typically 20 kg (45 lb), a women's Olympic bar 15 kg (35 lb), and many commercial gym bars weigh 10–15 kg. An incorrect bar weight is the most common reason training log numbers don't add up.
Colour coding. Plates are coloured to the International Weightlifting Federation (IWF) standard: 25 kg red, 20 kg blue, 15 kg yellow, 10 kg green and 5 kg white. The same cycle repeats on the change plates: 2.5 kg red, 2 kg blue, 1.5 kg yellow, 1 kg green and 0.5 kg white. The 1.25 kg plate common in powerlifting is not part of the IWF standard, so it appears here in chrome. Pound plates have no equally established standard; the calculator uses the common equivalent. Colour is always supplementary – the weight is printed on each plate as a number, so nothing depends on telling colours apart.Frequently asked questions
Do collars need to be included?
Competition collars weigh 2.5 kg each, or 5 kg per pair, which is a meaningful share of a light load. Ordinary spring clips weigh a few hundred grams and can usually be ignored. The calculator takes collar weight as a pair.
Why does the calculator suggest a different weight than I asked for?
Because your target cannot be built from the selected plates. With a 20 kg bar and 1.25 kg as the smallest plate, for example, the smallest possible increment is 2.5 kg. In that case the calculator shows the nearest achievable weight.
How do I work out the weight when I only know what plates are on the bar?
Use the second calculator on this page, Plates → weight. Enter how many of each plate and the bar weight, and you get the total. It also lists every other weight those plates can build, which is useful in a home gym with a limited plate selection.
How much is three plates?
In gym shorthand a plate means a 45 lb plate on each side of a 45 lb bar, so three plates is 315 lb, or 143 kg. One plate is 135 lb, two plates 225 lb, four plates 405 lb. The metric equivalents, using a 20 kg bar and 20 kg plates, are 60, 100, 140 and 180 kg.
Results are estimates and do not replace advice from a coach or healthcare professional.