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Discount one future payment to today using a fixed annual rate. The rate and horizon must use consistent annual periods.
Value equal payments made at the end of each period. At zero interest, present value equals the sum of payments.
Project equal contributions deposited at the end of each period. Contributions and return rate must refer to the same period.
Find a monthly contribution needed to close a savings gap without assuming investment returns or inflation.
Calculate equal monthly principal-and-interest payments for a fixed-rate loan. Fees and insurance are excluded.
Estimate remaining principal just after the kth scheduled monthly payment. Assumes no extra payments, missed payments or fees.
Estimate one monthly interest-only payment. This payment does not reduce principal and does not include fees.
Measure net return relative to the total invested cost. This does not annualize the return or account for cash-flow timing.
Find a constant annual growth rate between two positive values. Intermediate deposits and withdrawals are excluded.
Adjust a nominal return for inflation over the same time period. Both rates are entered by you, not retrieved live.
Estimate future purchasing power of an unchanged cash amount under a constant assumed inflation rate.
Calculate the exact time to double under constant annual compound growth. This is a projection, not a promise of return.
Measure profit as a percentage of revenue. Include every cost relevant to the margin you intend to measure.
Set a selling price by adding a percentage of cost. Markup on cost differs from profit margin on revenue.
Find whole units needed to cover fixed costs. Selling price must exceed variable cost per unit.
Compare packages by cost per unit of quantity. Use the same unit, such as kilograms or pieces, for every package compared.
Apply a second discount to an already discounted price. Discount percentages cannot simply be added.
Allocate depreciable cost evenly over useful life. Salvage cannot exceed cost; this is a general model, not a local tax schedule.
Estimate simple payback with constant annual cash flows. It ignores discounting and cash flows after recovery.
Compare an entered annual dividend with an entered share price. Dividend amounts may change and no live market data is used.
Compute a price-to-earnings ratio for positive earnings. Ensure price and earnings refer to the same share basis and currency.
Subtract outstanding liabilities from asset values measured at the same date. This does not assess liquidity or future income.
Calculate a reserve target using the number of months you choose and subtract existing savings. The tool does not prescribe a target.
Convert annual gross pay to an hourly equivalent based on paid hours. Taxes, overtime premiums and benefits are excluded.
Estimate gross overtime pay using a multiplier you provide. This does not determine statutory eligibility or local labor rules.
Convert money with an exchange rate entered manually and a percentage fee. No live rate or bank quotation is retrieved.
Divide total distance by total elapsed time, including stops. This is average speed, not instantaneous speed.
Calculate average acceleration along one axis. Signed velocities must refer to the same positive direction.
Calculate displacement and final velocity under constant acceleration in one dimension. Displacement may differ from total distance.
Estimate fall time and speed from rest with constant gravity and no air resistance. Real objects may behave differently.
Estimate an ideal projectile range when launch and landing heights match. Air resistance, wind and curvature are excluded.
Calculate net force from mass and acceleration in SI units under classical mechanics.
Calculate classical translational kinetic energy. The model is intended for speeds far below the speed of light.
Calculate gravitational potential energy relative to a chosen height reference, assuming constant local gravity.
Calculate signed linear momentum along one axis. Mass is nonnegative and velocity sets the direction.
Calculate impulse using average force over a time interval. It equals the change in momentum along the same axis.
Calculate work by a constant force along a straight displacement. Perpendicular forces do zero work in this model.
Find average power from work transferred during a positive time interval. The result is watts when inputs are joules and seconds.
Calculate average density from mass divided by occupied volume. Use kilograms and cubic metres for an SI result.
Calculate uniform pressure from the force normal to a surface. The area must be expressed in square metres.
Estimate the pressure increase below a fluid surface. Atmospheric or other surface pressure must be added separately for absolute pressure.
Calculate the buoyant force from displaced fluid volume. This is the upward force, not the net force on the object.
Calculate torque magnitude using the angle between position vector and force. At 90 degrees the lever arm is fully effective.
Find the inward net force required for circular motion at the entered speed and radius.
Apply Hooke’s law within a spring’s elastic range. The restoring force opposes displacement and stored energy is nonnegative.
Estimate the period of a simple pendulum for small angular oscillations, negligible friction and a point-like mass.
Find wavelength from wave speed and frequency in the same medium. Wave speed is an input rather than a universal constant.
Convert cyclic frequency to period and angular frequency. Hertz means cycles per second, not radians per second.
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