Free tool
Barbell Plate Calculator
Enter a target weight and bar — get the exact plate stack per side, visualized on a bar. lb or kg, with a toggle for excluding plates your gym doesn't stock.
Calculator
Load the bar
Available plates at your gym
Click to exclude plates your gym doesn't stock — the calculator will reload using only what's left.
Per side
90 lb
Load per side
What it looks like on the bar
One side shown — both sides load identically.
Under the hood
How this calculator works
The math is straightforward: target minus bar, divided by two, then greedy plate selection — largest first — until we run out of room.
- Per-side weight = (target − bar) ÷ 2
- Starting from the largest plate, take as many as fit without going over
- Move to the next plate down, repeat
- If the remainder is non-zero at the end, your available plates can't reach the exact target — the tool tells you how close it got
The “available plates” toggles let you constrain the search to what your gym actually stocks, so the result is always usable, not theoretical.
Standard plate sets
Imperial (lb)
- 45 lb — full-size plate
- 35 lb — full-size or “change” plate
- 25 lb — smaller diameter
- 10 lb — change plate
- 5 lb — change plate
- 2.5 lb — fractional plate
Metric (kg)
- 25 kg — red, full-size
- 20 kg — blue, full-size
- 15 kg — yellow, full-size
- 10 kg — green, change plate
- 5 kg — white, change plate
- 2.5 kg — red, fractional
- 1.25 kg — chrome, fractional
Related tools & reads
Load the bar, then use these to program the session:
- 1RM calculator → find target weights for any percentage
- Progressive overload guide → how to add weight intelligently
- Compound vs isolation exercises → what to prioritize for strength
Frequently asked
Questions people ask about this
How does a plate calculator work?
Subtract the bar weight from your target, divide by two (both sides load the same), then greedily pick the largest available plate that still fits — repeat until you're out of room. The calculator does this instantly and shows you exactly what to grab.
What's the standard Olympic bar weight?
A men's Olympic barbell is 45 lb (20 kg). A women's Olympic barbell is 35 lb (15 kg) — it's shorter and thinner for easier grip. Technique bars are typically 25-33 lb (10-15 kg) with Olympic-spec sleeves for learning. If you're not sure what your gym uses, ask — most commercial gyms have both men's and women's bars on the floor.
Do I need the same plates on both sides?
Yes, always — unbalanced loading causes the bar to tip and is a serious injury risk. Both sides should be mirror-image identical: same plate weights, loaded in the same order, with a collar locking them in place. The calculator assumes symmetric loading.
Why doesn't my exact target load cleanly sometimes?
The smallest standard plate in most commercial gyms is 2.5 lb (or 1.25 kg), so any total that isn't a multiple of 5 lb / 2.5 kg above the bar weight can't be loaded exactly. Either round to the nearest multiple or bring fractional plates (1.25 lb in lb gyms, 0.5-1 kg in kg gyms) if you need micro-progression.
What's the correct way to load plates?
Largest plates closest to the bar sleeve collar, smallest on the outside. This keeps the bar balanced front-to-back, distributes force through the heaviest plates first, and makes adding or removing weight faster. Always secure with a collar or spring clip before lifting.
How do I convert between pounds and kilograms?
1 kg = 2.2046 lb, and 1 lb = 0.4536 kg. Most people round: a 20 kg bar is called 45 lb (actually 44.1 lb), and 100 kg is called 225 lb (actually 220.5 lb). In powerlifting meets, kg is the official unit. In most US commercial gyms, lb is standard. The calculator converts automatically when you toggle units.
My gym only has a few plate sizes — can this still help?
Yes. Use the "available plates" toggles to exclude anything your gym doesn't stock. The calculator re-runs with just the remaining plates and tells you how close it can get to your target. If you can't hit the exact number, the result shows the gap so you know what to add (or what small plates to bring yourself for micro-loading).
What plate colors mean what?
International Weightlifting Federation (IWF) and IPF powerlifting use a color-coded kg system: red 25 kg, blue 20 kg, yellow 15 kg, green 10 kg, white 5 kg. Fractional plates — 2.5 kg, 1.25 kg, 0.5 kg — are smaller and use red/white/green respectively. US commercial-gym lb plates don't follow a standard color system — colors vary by brand.
Always lift with collars or spring clips in place — an unsecured plate can slide mid-rep and tip the bar. Match plate weights on both sides. If a weight feels wrong once the bar is loaded, check your stack before pulling.