Barbell plate calculator
The weight you want, the bar you are using, the plates your gym owns: the exact loading, per side.
Updated 26 September 2026
Turn off the ones your gym does not have: the calculation adapts to what you actually have to hand.
Why this is more annoying than it looks
Loading a bar takes three mental steps in a row: subtract the bar, halve the rest, then break that down into plates you actually have. That is easy at rest. Much less so between two heavy sets, out of breath, with someone waiting for the rack.
That is where the classic mistakes come from: forgetting the bar, loading one side wrong, or realising halfway through a set that the weight was not what you thought.
Bar weights
| Bar | Weight | Note |
|---|---|---|
| Olympic | 20 kg · 45 lb | The standard, 2.2 m |
| EZ curl | 9 kg · 20 lb | Biceps, triceps |
| Hex / trap | 25 kg · 55 lb | Deadlifts, farmer's walks |
| Smith | ≈ 20 kg quoted | Counterweighted: feels far lighter |
| Short straight bar | 13 kg · 30 lb | 1.2 to 1.5 m |
| Plate machine | 0 kg | Only the plates count |
The Smith machine deserves a word. Its bar is quoted at 20 kg, but the carriage counterweight cancels much of that — sometimes almost all of it, depending on the model. Loads there feel systematically easier, and comparing a Smith bench press to a free barbell bench press makes little sense.
The minimum increment
A detail that explains a lot of plateaus: you cannot progress in small steps without small plates. With 2.5 kg as your smallest plate, the smallest possible increase is 5 kg on the total. On a 60 kg bench press that is a jump of over 8% — far too much for a weekly progression.
With 1.25 kg plates the step drops to 2.5 kg. With 0.5 kg micro-plates, to 1 kg. It is the single best purchase for anyone stalling on upper-body lifts.
Loading order
Heaviest to lightest, closest to the centre. Two reasons: big plates near the sleeve reduce leverage and whip, and anyone can verify the load at a glance — including whoever is spotting you.
And of course: both sides before you lift. A bar loaded on one side only is the great classic of gym accidents.
The other tools
- One-rep max calculator — your estimated max, from an ordinary set.
- Rest times between sets — how long to wait, and why.
Frequently asked questions
How much does a barbell weigh?
A standard Olympic bar weighs 20 kg (45 lb). An EZ curl bar, around 9 kg. A hex or trap bar, around 25 kg. A short straight bar, about ten kilos. And a Smith machine bar, usually quoted at 20 kg, effectively weighs almost nothing for the lifter because of the counterweight — which is why everything feels easier on it.
Why does the total not always come out exactly?
Because not every weight is reachable. With 1.25 kg as your smallest plate, the smallest possible step is 2.5 kg on the total. Asking for 101 kg on a 20 kg bar is therefore impossible: the calculator tells you the total it actually reached and what is missing, instead of showing a wrong number.
Do collars count?
Light screw collars weigh a few hundred grams and can be ignored. Competition collars weigh 2.5 kg a pair — at that point they matter. If in doubt, weigh them once and stop wondering.
Why load the heaviest plate first?
Two reasons. Mechanics: big plates closer to the centre reduce the leverage and the whip on the bar. And legibility — anyone can check the load at a glance, including whoever is spotting you.