Free Gym Calculators: 1RM, Plates, Volume | Strongbro
Free calculators that run in your browser. Nothing is uploaded, nothing is stored.
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One Rep Max Calculator: Estimate Your 1RM Safely (Free)
Enter a weight and 1 to 15 reps to get your estimated one-rep max, averaged from the Brzycki and Epley formulas, plus a percentage table for 2 to 15 rep sets.
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1RM Percentage Chart: What Weight for 5, 8, 10 or 12 Reps
A full percentage-of-1RM chart from 100% down to 60%, with the rep count each row supports and worked weights for a 60 to 140 kg max. Plan a session in 2 minutes.
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How to Test Your One Rep Max Safely in 2026 (Step by Step)
A 6-step warm-up ladder, the rack and spotter setup that makes a max attempt safe, and the 5 situations where an estimate from a set of 3 to 5 beats testing at all.
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Barbell Plate Calculator: Plates per Side, kg and lb (Free)
Type a target weight, pick a 20 kg, 15 kg or 45 lb bar, and see exactly which plates to load per side. Standard 7-plate kg set and 6-plate lb set, with a diagram.
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How Much Does a Barbell Weigh? Every Common Bar Listed (2026)
A standard Olympic bar weighs 20 kg or 45 lb, but EZ bars run 7 to 12 kg, trap bars 20 to 30 kg and Smith machine bars vary widely. Every bar in one table.
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What Does “Two Plates” Mean? Plate Slang in kg and lb
Two plates means two big plates per side: 100 kg in a metric gym, 225 lb in a US gym. One to five plates in both units, per side versus total, in 1 table.
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Training Volume Calculator: Sets × Reps × Weight (Free)
Free training volume calculator: one row per exercise (weight × reps × sets), total tonnage, sets and reps in 10 seconds. Browser-only, nothing uploaded.
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How Many Sets per Week per Muscle? What the Research Says (2026)
The research behind the 10-20 sets per muscle per week range: what the meta-analyses found, how ranges shift with training age, and how to count a hard set.
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Volume vs Intensity: Which One Should You Track? (2026)
Volume is sets × reps × weight; intensity is load as a percentage of your 1RM. Both drive progress in different ways. The 2 numbers a log needs to capture each.
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