Online Tool Store
Weight Plate Calculator
Calculate plates per side for a target barbell weight and review a visual stack using common lb or kg plate sizes. Review the result before using it.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Example shown — standard plate set assumed (45/35/25/10/5/2.5 lb or 25/20/15/10/5/2.5/1.25 kg).
Per side of the bar
—
How it works
- Enter your target total weight and the bar's own weight.
- See exactly how many of each plate size to load per side.
- Switch units between lb and kg — the bar weight default updates to match.
The formula
Per side = (Target weight − Bar weight) ÷ 2
That per-side weight is then greedily broken down into the largest plates first, then the next largest, and so on — the same way you'd load a bar by hand.
FAQ
What plate sizes does this assume?
A standard commercial gym set: 45, 35, 25, 10, 5, and 2.5 lb, or 25, 20, 15, 10, 5, 2.5, and 1.25 kg. If your gym only has some of these sizes, the suggested combination may not match what's actually on the rack.
What does "leftover" weight mean?
It shows up when the exact per-side weight can't be made from the available plate denominations (e.g. needing 1.3 kg per side with only 1.25 kg as the smallest plate) — a sign to round to the nearest weight your gym's plates actually allow.
Why divide by 2 for the per-side weight?
A barbell has two ends, and the same plates go on both sides to keep it balanced — so half of the weight beyond the bar itself needs to be loaded on each side.
What's a standard bar weight?
A full-size Olympic barbell is 45 lb (20 kg) — the default here — but some gyms also have lighter "women's bars" (35 lb / 15 kg) or technique bars. Change the bar weight field to match whichever one you're using.
How we compare
| Feature | Online Tool Store | Gym whiteboard math | Fitness app plate calculators |
|---|---|---|---|
| Visual plate stack, not just a number | ✓ | Manual, error-prone | Varies by app |
| No app install | ✓ | ✓ | App install required |
| No ads | ✓ | ✓ | Ad-supported free tier |
Faster than doing the mental math between sets, and no app to install just to load a bar.