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Estimate transfer time from file size, connection speed, and assumed transfer efficiency. Decimal units use 1 MB = 1,000,000 bytes and 1 GB = 1,000,000,000 bytes; 1 GiB = 1,073,741,824 bytes. Efficiency accounts for protocol overhead and other slowdowns. Defaults are illustrative, and actual transfer speeds can vary.

Estimate the total storage capacity needed for existing data and new files, including copies and free-space headroom. File sizes use decimal units: 1 GB = 1,000 MB. Enter the total number of copies, including the original. The estimate assumes every copy occupies the same space and does not account for compression, filesystem overhead, or future growth beyond the amounts entered.

Estimate UPS battery runtime from battery-bank voltage and capacity, connected load, usable battery capacity, and inverter efficiency. Defaults are illustrative. Actual runtime varies with battery age, discharge rate, temperature, and UPS design; manufacturer runtime charts provide a better estimate when available.

Estimate the electricity cost of running a PC using its average power draw, daily usage, billing period, and electricity rate. Defaults are illustrative. Include the monitor and peripherals in the power draw if you want their costs included. Actual power draw and electricity rates may vary.

Estimate daily electricity use from average CPU, GPU, and other component power. Power supply efficiency converts component power to estimated power drawn from the wall. Defaults are illustrative; actual use varies with workload and hardware.

Estimate the minimum continuous DC output rating for a desktop workstation power supply using component power estimates and a target load percentage. Enter the combined power of all CPUs and GPUs if applicable. Defaults are illustrative. Choose an available PSU rating at or above the result, and check component power spikes, connectors, and manufacturer recommendations separately. This estimate does not apply to laptop charger sizing.

Estimate the minimum dock power-adapter output needed to supply your laptop, dock, and connected accessories. Enter the laptop’s manufacturer-rated charging power and the maximum simultaneous power draw of the dock and accessories. The efficiency and headroom defaults are illustrative assumptions; check the dock manufacturer’s specifications before choosing an adapter.

Estimate the total cost of a laptop workstation using your own prices, sales tax rate, and contingency allowance. Defaults are illustrative. The estimate assumes sales tax applies to all listed purchases and that contingency is calculated on the after-tax total.

Calculate a laptop screen’s pixel density in pixels per inch (PPI) from its resolution and diagonal size. This uses the Pythagorean theorem and assumes square pixels. The default values are illustrative.

Calculate the viewable screen height and width from its diagonal size and aspect ratio. Results are in inches and exclude the bezel. Enter the aspect ratio from the screen specifications; defaults are illustrative.

Estimate a laptop’s current resale value using declining-balance depreciation. Enter your purchase price, age, assumed annual depreciation rate, and any additional condition-related deduction. The result is an estimate based on your assumptions, not a live market price.

Estimate the electricity cost of running a laptop using its average power draw, daily usage, billing period, and electricity rate. Use power measured at the wall when available; charger ratings are maximum outputs and may overestimate typical consumption. The estimate assumes a constant average power draw and excludes separate peripherals.

Estimate the power bank capacity needed for a chosen number of full laptop battery charges. The calculation accounts for energy lost during conversion and charging, then converts watt-hours to milliamp-hours at the power bank’s stated cell voltage. Defaults are illustrative. Actual results vary with laptop use, charging behavior, and power bank efficiency. Choose a power bank with at least the calculated capacity and check that its USB-C output voltage and wattage meet your laptop’s requirements.

Estimate charger wattage from the laptop’s required input voltage and current, with an optional headroom allowance. Check the laptop’s manufacturer specifications and choose a charger that supports the required voltage, connector, polarity, and charging protocol. Round up to an available charger wattage. Defaults are illustrative.

Estimate charging time from battery capacity, current and target charge, charger power, charging efficiency, and a taper factor. Charger power is the power available for charging after laptop use. Efficiency and taper are illustrative assumptions; charging slows near full capacity, and actual times vary. If the target is at or below the current charge, the estimate is zero.