One Rep Max (1RM) Calculator
Estimate your single repetition maximum lifting capacity using Epley, Brzycki, and Lander models. View your strength-to-weight ratio.
• Epley: $1RM = w \times (1 + r / 30)$ - Standard industry equation.
• Brzycki: $1RM = w / (1.0278 - 0.0278 \times r)$ - Extremely accurate under 10 repetitions.
• Lander: Better tracks elite explosive lifting velocities.
Explore Additional Utilities
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Determine required starting paper square dimensions to fold specific final 3D origami model sizes.
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Convert between Lux and Foot-candles, and compute beam diameter coverage footprint at specific throw distances.
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Convert between filament physical weight in grams and equivalent spool length in meters based on material density and diameter.
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