Calculators
Planning tools for laptop power & mobile computing, with visible assumptions and units.
Estimate the storage capacity needed for backup copies by combining the data you plan to protect, the number of copies, and an additional reserve percentage. This is a planning estimate and does not account for file-system overhead or device-specific usable capacity.
Estimate a laptop battery's current full-charge capacity as a percentage of its original design capacity. Enter both capacities in watt-hours (Wh).
Estimate a computer's electricity cost for a selected period using its power draw, hours of daily use, electricity price, and number of days. The estimate assumes the entered wattage is the computer's average power draw.
Estimate a planning budget for replacing a computer by combining a base computer cost with selected component, accessory, and setup allowances. This worksheet uses your entered amounts and does not quote market prices.
Estimate the cable length needed to connect a desk device to a power outlet or hub by adding the measured route distance, vertical travel, and slack. The result is a planning estimate and does not account for connector-specific requirements or cable routing rules.
Estimate the ideal time to download a file from its size and connection speed. This estimate assumes a steady connection and does not account for network overhead or slowdowns.
Estimate the ideal time to transfer a file from its size and the available data transfer rate. Enter file size in megabytes and speed in megabits per second to see the result in seconds.
Estimate laptop runtime in hours from battery capacity, current charge, and average power draw. This transparent estimate assumes a steady load and does not account for battery age, conversion losses, or changing workloads.
Estimate the electricity cost of using a laptop charger over a planning period. Enter the charger's rated input power, hours plugged in per day, number of days, and your electricity price. This simplified estimate treats the charger as drawing its rated input power for every entered hour; actual consumption varies with laptop load, charging state, and standby behavior.
Estimate the time needed to charge a laptop battery from its current charge level to a higher target level using battery capacity and average charging power.
Estimate the energy your laptop setup needs during a trip from device power draw, daily use, travel days, and the share of time you expect to run on battery. The estimate is in watt-hours and does not account for battery losses or power-bank conversion efficiency.
Convert a battery's capacity from milliamp hours (mAh) to watt hours (Wh) using its nominal voltage. Enter capacity and voltage to calculate the energy equivalent.
Calculate a monitor’s pixel density in pixels per inch (PPI) from its horizontal and vertical resolution and diagonal screen size.
Convert a network bandwidth or transfer rate between decimal bit-per-second and byte-per-second units, from bits per second through gigabytes per second.
Estimate the energy a power bank can deliver to a device after accounting for conversion efficiency. Enter the rated battery capacity, nominal battery voltage, and estimated efficiency. The result is an approximate usable energy in watt-hours.
Calculate a laptop screen's aspect ratio from its width and height in pixels, and see the matching simplified ratio.
Calculate an SSD's price per gigabyte from its purchase price and advertised capacity. Enter the price and capacity in decimal gigabytes to get a straightforward unit-cost comparison.
Estimate backup runtime in hours from battery voltage, rated capacity, connected load, and an assumed usable-energy efficiency. The result is a simplified estimate, not a manufacturer runtime guarantee.
Estimate nominal electrical power in watts from USB voltage and current using P = V × I. Enter compatible voltage and current values from a charger, port, or device label. This arithmetic estimate does not determine USB power negotiation or actual device consumption.
Convert energy in watt-hours to an equivalent battery capacity in milliamp-hours using the battery voltage you provide.