槓鈴槓片計算機

What the plate calculator does

When you walk up to the bar with a working weight in mind, you need to translate “120 kg” or “275 lb” into “which plates go on each side, in what order.” Most lifters do this in their head — and most lifters get it wrong sometimes, especially after a few sets when they’re tired or under heavy weight. The plate calculator removes that mental tax.

The math:

weight per side = (target − bar) / 2

Then a greedy plate-loading algorithm walks the standard plate sizes from heaviest to lightest, fitting as many as possible at each step. The result is the minimum number of plates that reach the target weight, plus a remainder if the target isn’t exactly achievable.

Standard plate sets

Kilogram plates (IPF standard, used in international powerlifting)

Plate (kg)	Color (competition)	Common gym variant
25	Red	Black or red
20	Blue	Blue or black
15	Yellow	Yellow or grey
10	Green	Green or black
5	White	White or black
2.5	Red (small)	Red or black
1.25	Chrome / black (small)	Black

A standard men’s bar weighs 20 kg. Loaded with two 25s and one 20 per side, you reach 20 + (50 + 20)×2 = 160 kg.

Pound plates (standard US/UK)

Plate (lb)
45
35
25
10
5
2.5

A standard men’s bar weighs 45 lb. Loaded with four 45s per side, you reach 45 + (180×2) = 405 lb.

A worked example

You want to bench 102.5 kg on a 20 kg bar. The calculator computes:

weight per side = (102.5 − 20) / 2 = 41.25 kg

Greedy fit:

• 25 kg plate fits → remaining 16.25 kg
• 15 kg plate fits → remaining 1.25 kg
• 1.25 kg plate fits → remaining 0 kg

Per side: one 25, one 15, one 1.25. Total bar load: 20 + 41.25×2 = 102.5 kg.

You want to squat 315 lb on a 45 lb bar:

weight per side = (315 − 45) / 2 = 135 lb

Greedy fit: three 45-lb plates per side. Per side: 3 × 45 lb. Total: 45 + 135×2 = 315 lb. The classic three-plates-a-side squat.

You want to deadlift 177.5 kg on a 20 kg bar:

weight per side = (177.5 − 20) / 2 = 78.75 kg

Greedy fit:

• 25 kg → remaining 53.75
• 25 kg → remaining 28.75
• 25 kg → remaining 3.75
• 2.5 kg → remaining 1.25
• 1.25 kg → remaining 0

Per side: three 25s, one 2.5, one 1.25. Some gyms don’t stock 1.25 kg plates; in that case, round to 175 kg or 180 kg.

How to use this calculator

1. Toggle metric or imperial.
2. Enter your target total weight (the number you want on the bar).
3. Enter your bar weight — typically 20 kg, 15 kg, 45 lb, or 33 lb.
4. Read the per-side breakdown as a list of plates.
5. Watch for the remainder: if non-zero, the target isn’t exactly achievable with the standard plate set. The calculator shows the closest achievable load.

Loading order matters (a little)

When you load the bar, the convention is to put the heaviest plates closest to the collar (the inside of the sleeve), and lighter plates outside. Three reasons:

• Stability: the heaviest weight is closest to the bar’s pivot, so the loaded bar is more stable on the rack.
• Aesthetics / convention: lifters know what “three plates a side” means; the visual shorthand assumes heaviest plates inside.
• Safety: with the heavy plates inside, the bar bends slightly under load; lighter plates outside flex more, but they’re under less inertial stress.

Always collar your plates. A bar with uncollared plates that catches one side on a missed lift is a serious injury risk, especially for squats and bench.

Common loading shortcuts

Memorizing a few common loadings saves mental work mid-session:

• 20 kg bar + 1 × 20 per side = 60 kg
• 20 kg bar + 1 × 25 per side = 70 kg
• 20 kg bar + 2 × 20 per side = 100 kg
• 20 kg bar + 1 × 25 + 1 × 20 per side = 110 kg
• 20 kg bar + 2 × 25 per side = 120 kg
• 20 kg bar + 2 × 25 + 1 × 10 per side = 140 kg
• 20 kg bar + 3 × 25 per side = 170 kg
• 20 kg bar + 3 × 25 + 1 × 10 per side = 190 kg
• 20 kg bar + 4 × 25 per side = 220 kg

In pounds:

• 45 lb bar + 1 × 45 per side = 135 lb
• 45 lb bar + 2 × 45 per side = 225 lb
• 45 lb bar + 3 × 45 per side = 315 lb
• 45 lb bar + 4 × 45 per side = 405 lb
• 45 lb bar + 5 × 45 per side = 495 lb

When the calculator helps most

• Mid-session weight changes. Adding 5 kg to your last set, fatigued, with the bar still loaded — fast plate math saves cognitive energy you’d rather spend on the rep.
• Conjugate / Bulgarian-style training. When loads change every set or every week, repeated mental math compounds errors.
• Programming weeks. Pre-printed plate breakdowns for your training log mean zero ambiguity at the bar.
• Coaching and writing programs. “180 kg per side, 4×6” assumes the lifter can compute the loading; spelling it out removes any doubt.

Edge cases the calculator handles

• Non-standard bars. Plug in any bar weight (e.g., 10 kg training bar, 15 kg women’s bar, 45 lb power bar, etc.).
• Half-pound and 0.5 kg microplates. Disabled by default; available as an option for fine-tune deload work.
• Non-symmetric loading. Not supported. The calculator assumes you load identical plates on both sides — which you should always do for safety.

The bar math isn’t hard, but it’s also one more thing to think about between sets. Letting a calculator handle it leaves more energy for the lifting itself.