Battery Calculators & Engineering Tools
Free calculators for solar, home backup, RV, marine, EV, battery packs, and energy storage systems.
Popular Battery Tools
Tools by Category
VIEW ALL TOOLS →Solar
Sizing, off-grid planning, and home backup with PV + storage
Home Backup
Essential loads, runtime planning, and outage preparedness
RV
Van/camper energy planning, runtime estimates, inverter matching
Marine
Boat electrical planning, load estimation, and battery sizing
EV
Pack design, series/parallel configuration, voltage planning
BESS
Commercial ROI, peak shaving, and demand charge planning
Engineering
C-rate, SOC/SOH, voltage drop, and cable loss analysis
Featured Calculators
VIEW ALL →Runtime Calculator
Estimate discharge runtime from capacity, load, and efficiency.
Battery Sizing Calculator
Size battery banks from daily loads, autonomy, and temperature.
C-Rate Calculator
Calculate charge/discharge current and C-rate speed.
DC Voltage Drop Calculator
Calculate voltage drop across DC conductors.
DC Cable Loss Calculator
Determine resistive power losses in DC lines.
BESS ROI Calculator
Evaluate NPV and payback for commercial battery storage.
Learning Center
VIEW ALL GUIDES →Trustworthy Calculations, Built for Engineering Work
Transparent Formulas
All equations and assumptions are visible.
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Engineering References
Based on established electrical engineering principles.