Power Tool Battery Runtime Calculator
Estimate cordless power tool runtime using a standardized intermittent-use benchmark. Compare different battery capacities across common power tools using the same calculation method.
PKZON Standardized Intermittent Benchmark
Power tools do not normally consume maximum electrical power continuously. An impact driver, for example, draws power while fastening and then stops when the trigger is released.
To make battery comparisons more meaningful, this calculator uses a fixed 60-second intermittent-use benchmark for each tool category. The same benchmark is applied regardless of battery brand or capacity.
These are PKZON calculation benchmarks, not manufacturer-rated runtime figures.
Standard Benchmark Cycles
| Tool | Active | Rest | Duty Cycle |
|---|---|---|---|
| Impact Driver | 10 sec | 50 sec | 16.7% |
| Drill / Driver | 15 sec | 45 sec | 25% |
| Impact Wrench | 10 sec | 50 sec | 16.7% |
| Circular Saw | 30 sec | 30 sec | 50% |
| Reciprocating Saw | 30 sec | 30 sec | 50% |
| Angle Grinder | 40 sec | 20 sec | 66.7% |
| Blower | 50 sec | 10 sec | 83.3% |
How Battery Runtime Is Calculated
Battery energy is calculated from its nominal voltage and capacity:
Battery Energy (Wh) = Voltage (V) × Capacity (Ah)
The calculator assumes 85% of nominal battery energy is practically usable. This accounts for conversion losses, battery protection, discharge characteristics and other real-world factors.
The tool's benchmark power consumption is then adjusted according to its fixed intermittent duty cycle.
Why Impact Driver Runtime Can Be Much Longer
An impact driver is an intermittent-use tool. It may operate for only a few seconds while driving a fastener and remain idle while the user positions the next fastener.
Therefore, calculating runtime from continuous maximum power can produce extremely short and misleading results. This calculator instead applies a fixed intermittent benchmark so the result better represents elapsed jobsite use.
FLEXVOLT Battery Calculation
FLEXVOLT batteries can operate at different system voltages depending on the tool. The calculator therefore uses the battery's approximate total energy rather than simply multiplying a displayed Ah value by 60V.
For example, a FLEXVOLT 6Ah pack is treated as approximately 120Wh for energy calculations. This avoids overstating its energy as 360Wh.
Important Limitations
Actual runtime varies with tool model, material, workload, fastening size, cutting depth, trigger time, battery temperature, battery age, battery condition and operator technique.
Manufacturer runtime tests may use different tools, materials, operating cycles and test conditions. Therefore, PKZON benchmark results should be used for comparison and planning rather than as guaranteed runtime figures.
Frequently Asked Questions
Why does my power tool run longer than a continuous-power calculation?
Because many cordless tools operate intermittently. They consume significant power while working but consume little or no power while the trigger is released. A continuous-power calculation ignores this usage pattern.
Does a higher Ah battery always last longer?
Generally, a higher-capacity battery stores more energy when comparing batteries with the same nominal voltage and similar technology. Actual performance also depends on battery design, tool compatibility and load.
Is this an official Milwaukee or DEWALT runtime calculator?
No. This is a PKZON standardized estimation tool. It does not reproduce manufacturer laboratory tests or guarantee actual runtime.
Can I calculate runtime for another battery?
Yes. Select Custom Battery and enter its nominal voltage and capacity in Ah. The calculator will convert these values into estimated battery energy.
Power Tool Battery Runtime Calculator
Estimate cordless power tool runtime using a standardized intermittent-use benchmark. Compare different battery capacities across common power tools using the same calculation method.
PKZON Standardized Intermittent Benchmark
Power tools do not normally consume maximum electrical power continuously. An impact driver, for example, draws power while fastening and then stops when the trigger is released.
To make battery comparisons more meaningful, this calculator uses a fixed 60-second intermittent-use benchmark for each tool category. The same benchmark is applied regardless of battery brand or capacity.
These are PKZON calculation benchmarks, not manufacturer-rated runtime figures.
Standard Benchmark Cycles
| Tool | Active | Rest | Duty Cycle |
|---|---|---|---|
| Impact Driver | 10 sec | 50 sec | 16.7% |
| Drill / Driver | 15 sec | 45 sec | 25% |
| Impact Wrench | 10 sec | 50 sec | 16.7% |
| Circular Saw | 30 sec | 30 sec | 50% |
| Reciprocating Saw | 30 sec | 30 sec | 50% |
| Angle Grinder | 40 sec | 20 sec | 66.7% |
| Blower | 50 sec | 10 sec | 83.3% |
How Battery Runtime Is Calculated
Battery energy is calculated from its nominal voltage and capacity:
Battery Energy (Wh) = Voltage (V) × Capacity (Ah)
The calculator assumes 85% of nominal battery energy is practically usable. This accounts for conversion losses, battery protection, discharge characteristics and other real-world factors.
The tool's benchmark power consumption is then adjusted according to its fixed intermittent duty cycle.
Why Impact Driver Runtime Can Be Much Longer
An impact driver is an intermittent-use tool. It may operate for only a few seconds while driving a fastener and remain idle while the user positions the next fastener.
Therefore, calculating runtime from continuous maximum power can produce extremely short and misleading results. This calculator instead applies a fixed intermittent benchmark so the result better represents elapsed jobsite use.
FLEXVOLT Battery Calculation
FLEXVOLT batteries can operate at different system voltages depending on the tool. The calculator therefore uses the battery's approximate total energy rather than simply multiplying a displayed Ah value by 60V.
For example, a FLEXVOLT 6Ah pack is treated as approximately 120Wh for energy calculations. This avoids overstating its energy as 360Wh.
Important Limitations
Actual runtime varies with tool model, material, workload, fastening size, cutting depth, trigger time, battery temperature, battery age, battery condition and operator technique.
Manufacturer runtime tests may use different tools, materials, operating cycles and test conditions. Therefore, PKZON benchmark results should be used for comparison and planning rather than as guaranteed runtime figures.
Frequently Asked Questions
Why does my power tool run longer than a continuous-power calculation?
Because many cordless tools operate intermittently. They consume significant power while working but consume little or no power while the trigger is released. A continuous-power calculation ignores this usage pattern.
Does a higher Ah battery always last longer?
Generally, a higher-capacity battery stores more energy when comparing batteries with the same nominal voltage and similar technology. Actual performance also depends on battery design, tool compatibility and load.
Is this an official Milwaukee or DEWALT runtime calculator?
No. This is a PKZON standardized estimation tool. It does not reproduce manufacturer laboratory tests or guarantee actual runtime.
Can I calculate runtime for another battery?
Yes. Select Custom Battery and enter its nominal voltage and capacity in Ah. The calculator will convert these values into estimated battery energy.