The plate colors and bar weights behind every loaded barbell

The International Weightlifting Federation fixes competition plate colors by weight in its Technical and Competition Rules: 25 kg is red, 20 kg blue, 15 kg yellow, 10 kg green, and 5 kg white. The point is legibility. A judge, a loader, and the lifter can read a bar from across the platform without counting.

Pound plates never got that treaty, so a 45 is black rubber in one gym and blue steel in the next. This page is the reference for both: the standard denominations, how the color code works, which bars weigh what, and why an exact number sometimes will not load.

Standard plate denominations, in pounds and kilograms

Two parallel sets cover almost every rack. The pound set runs 45, 35, 25, 10, 5, 2.5, and 1.25. The kilogram set runs 25, 20, 15, 10, 5, 2.5, and 1.25. They are not conversions of each other. A 45 lb plate is 20.41 kg, not a round 20, so a gym that stocks both keeps them apart and never mixes a pound plate onto a kilogram bar.

The pound plates here follow the same size-based palette as the kilogram set (the 45 takes the blue slot, the 25 the green) rather than the exact IPF pound code, because gym pound plates are rarely color-standardized and one consistent palette reads more clearly on the loaded-bar diagram.

The competition color code, and where gym plates ignore it

The IWF colors are load-bearing on a platform and decorative everywhere else. Calibrated competition plates hold the code to the gram and get certified for it. Commercial-gym bumpers and cast-iron plates follow it loosely at best: a 10 kg bumper is often plain black, a 45 lb plate just grey steel.

So read the code when it is there, and fall back to the number stamped on the plate when it is not. That split is why the tool colors its diagram by plate size rather than by any official code. The color is a reading aid; the weight is the fact.

Bar weights and the 20 kg that reads 44.09 lb

Every per-side result depends on the bar, because the bar comes off the target before the rest is split between the two sleeves. Here the two unit systems collide. A US “45 lb” men's bar really is 45 lb, which works out to 20.41 kg. A rated Olympic men's bar is exactly 20 kg, which is 44.09 lb, close to 45 but not equal to it. Program a 20 kg bar as 45 lb and every rep runs about a pound light.

The tool defaults to a 45 lb standard and a 35 lb women's preset, a 20 kg / 15 kg pair on the kilogram side, and a custom field for trap bars and safety squat bars; it is one of the free lifting calculators on AppCrib.com.

Smallest jumps and the plates that make them

Plates load in pairs, so the smallest change you can make to a bar is always twice the smallest plate you own. Stop at a 5 lb plate and your finest step is 10 lb. Add 2.5 lb plates and it halves to 5 lb; add 1.25 lb plates and it halves again to 2.5 lb. The kilogram side works the same way, where 0.5 kg and 0.25 kg micro plates buy 1 kg and 0.5 kg steps. This is the reason an exact target sometimes won't load: ask for 187.5 lb on a 45 lb bar and the math wants 71.25 lb a side, but with nothing smaller than a 5 the closest stack is 70 lb, which totals 185 and leaves you 2.5 short. We convert every unit toggle at 1 kg = 2.2046226218 lb, the factor set by the 1959 international pound agreement that defines the pound as exactly 0.45359237 kg, then round the display to the nearest half so the number you land on stays tidy.

One 1.25 lb plate on each side closes that 2.5 lb gap exactly.

Questions lifters ask

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