Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Electronics & Hardware Engineering
Battery Runtime Calculator — mAh Capacity vs Load Current
Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
Calculate how many hours a battery will run at a given load current. Planning estimates only — verify with production tools and vendor pricing where applicable.
Inputs
10050000
15000
50100
Smart analysis
Recommendations
Tailored to your live inputs and result—guidance only, not professional advice.
- Interpret
Treat this as a planning estimate
Primary result: Runtime = 17.0 hours. Re-run with optimistic and pessimistic inputs to understand the range—not just a single point.
Scenario studio
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Scenario A
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Scenario B
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Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
Battery capacity (mAh)
The “Battery capacity (mAh)” value used in this tool’s formula. Adjust it to see results update live.
Average load (mA)
The “Average load (mA)” value used in this tool’s formula. Adjust it to see results update live.
Efficiency (%)
The “Efficiency (%)” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
Calculate how many hours a battery will run at a given load current. Planning estimates only — verify with production tools and vendor pricing where applicable. Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor. Example: 3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
Example: 3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
When to use this Battery Life / Runtime Estimator
Common use cases
- Calculate how many hours a battery will run at a given load current.
- Sanity-check with this case: 3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
- The relationship is: Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
Localized examples
- Electronics & Hardware Engineering: the example on this page uses the same formula as the widget.
What you get
- Fields: Battery capacity (mAh), Average load (mA), Efficiency (%)
- Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
- Example on the page: 3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
How to Calculate Battery Life / Runtime Estimator Step-by-Step
- 1Enter Battery capacity (mAh), Average load (mA), Efficiency (%). Use the values you have, not a catalog average, unless that is all you know.
- 2Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
- 3Worked case: 3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
- 4Compare the result to last month’s invoice or a vendor calculator before you commit capacity.
Governing formula
Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
3000 mAh battery, 150 mA load, 85% efficiency → ~17 hours.
Example: set Battery capacity (mAh) = 3,000, Average load (mA) = 150, Efficiency (%) = 85, then read the result.
Variable definitions
- capacityMah
Battery capacity (mAh)
The “Battery capacity (mAh)” field. Default 3000; typical range 100–50000.
- loadMa
Average load (mA)
The “Average load (mA)” field. Default 150; typical range 1–5000.
- efficiencyPct
Efficiency (%)
The “Efficiency (%)” field. Default 85; typical range 50–100.
- Closed-form math (Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.) misses idle time, egress, packet loss, and reserved capacity on the real bill.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
Runtime (hrs) = capacity (mAh) ÷ load (mA) × efficiency factor.
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Community
Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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