Barbell Plate Calculator
Enter your target weight and see exactly which plates to load on each side of the bar — in kg or lb.
Standard bar: 20 kg
How the plate calculator works
The maths is simple: subtract the bar weight from your target, then divide by two — that's the weight you need per side. For 100 kg with a 20 kg bar, that's (100 − 20) ÷ 2 = 40 kg per side, which loads as one 25 kg and one 15 kg plate.
The calculator fills each side largest-plate-first, the same way you'd load a bar in the gym — fewer, bigger plates are more stable and quicker to change. If your exact target isn't reachable with standard plate sizes, it shows the closest achievable weight below it.
Not sure what weight to target? Estimate it with the one rep max calculator and work from your training percentages.
Standard barbell and plate weights
This calculator assumes a standard men's Olympic bar: 20 kg in kg mode and 45 lb in lb mode. Women's Olympic bars weigh 15 kg (33 lb), and many home-gym bars are lighter still.
Standard kg plates come in 25, 20, 15, 10, 5, 2.5, and 1.25 kg. Competition plates are color-coded to the IWF standard — red 25 kg, blue 20 kg, yellow 15 kg, green 10 kg, white 5 kg — and the diagram above uses the same colors. Standard lb plates come in 45, 35, 25, 10, 5, and 2.5 lb.
Plate calculator FAQ
How much does a barbell weigh?
A standard men's Olympic barbell weighs 20 kg (45 lb). The women's Olympic bar weighs 15 kg (33 lb). Many home-gym and specialty bars are lighter — EZ curl bars are usually 7–10 kg — so check yours before loading if the exact weight matters.
Why can't I always hit my exact target weight?
Your smallest plate pair sets the increment. If the smallest plates you have are 1.25 kg, the bar can only move in 2.5 kg steps (one plate per side). This calculator shows the closest achievable weight below your target with standard plate sizes.
What do the plate colors mean?
Competition kg plates follow the IWF color standard: red 25 kg, blue 20 kg, yellow 15 kg, green 10 kg, and white 5 kg. Many gym plates copy this scheme, which makes it faster to read a loaded bar at a glance — the diagram in this calculator uses the same colors.
What plates do I need for a home gym?
A common kg starter set is a pair each of 20, 10, 5, 2.5, and 1.25 kg, which covers a 20 kg bar up to 97.5 kg in 2.5 kg steps. Add pairs of 20s or 25s as you get stronger — and fractional plates (0.5–1.25 kg) are worth it for pressing movements that progress slowly.
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