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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Translate between SI physical units and the fundamental Planck natural units based on universal constants.
Script Character ↔ Word Counter
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NPK Fertilizer Blend Designer
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dBm to Watts/Volts
Convert RF power levels between dBm, milliwatts, watts, and RMS voltage across 50/75 ohm impedance.
Ballistic coefficient ↔ drag — projectile performance
Calculate bullet Sectional Density (SD) and Ballistic Coefficient (BC) using projectile weight, caliber, and form factor.
Ground acceleration — Gal ↔ g ↔ m/s²
Convert Peak Ground Acceleration (PGA) values among Gal, gravity fractions, and m/s².
Twist rate — caliber ↔ bullet length → stabilization
Calculate the optimal barrel rifling twist rate needed to stabilize a bullet of a given length, caliber, and velocity.
Cycling FTP & Power Zone Calculator
Calculate personalized cycling power training zones (Coggan 7-zone model) based on your Functional Threshold Power (FTP) in watts.
Power reserve — mainspring tension ↔ hours of run time
Compute total mainspring operational run time based on turns of wind, barrel capacity, and balance wheel beat rate demands.
U-value ↔ thermal performance — double vs triple glazing
Analyze thermal conductivity (U-values and R-values) for energy-efficient glazing window performance.
Pump Efficiency Calculator
Calculate pump efficiency and hydraulic power based on volumetric flow rate, head height, fluid density, and input shaft power.
Arrow spine ↔ draw weight + length — stiffness matching
Estimate required arrow static spine rating (stiffness) based on bow draw weight, arrow length, and bow type.
Pediatric Dosing Calculator
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Half Value Layer (Shielding)
Calculate radiation intensity reduction through shielding materials (lead, steel, concrete, water) using half-value thickness and attenuation.
Hold size ↔ finger force — crimp load estimation
Estimate skeletal finger force and crimp tendon pulley loads (A2/A4) based on edge/hold size (mm) and climber weight.
Gear ratio (input RPM ↔ output RPM ↔ torque)
Calculate gear ratios and convert input RPM and torque to output values based on compound single or double-stage tooth configurations.
Reynolds Number Simulator
Determine fluid flow regimes (laminar, transitional, or turbulent) by calculating the dimensionless Reynolds number from velocity, diameter, and viscosity.
Hallmark converter (UK date letters ↔ year)
Decode historic and modern UK silver, gold, and platinum hallmarks, converting assay office date letters to exact production years.
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Calculate descent drift offset distance, wind deflection angles, and flight heading corrections for precision landing dropzones.
Dewpoint & Relative Humidity Calculator
Calculate dewpoint, relative humidity, or air temperature using the Magnus-Tetens formula.