Online Math Tools

Calculate the absolute value of positive, negative, or decimal numbers and explain the sign relationship

Convert acres to hectares with configurable decimal precision

Convert acres to square feet with configurable decimal precision

Convert acres to square meters with configurable decimal precision

Calculate the Rankine active earth pressure on a smooth vertical wall backfilled with cohesionless soil. K_a = tan²(45°−φ/2). Optional uniform surcharge q. Returns the base pressure p₀, the total force P, and the resultant height.

Calculate adjusted R squared from R squared, sample size, and predictor count

Compute complex admittance Y = 1/Z = G + jB for series or parallel RLC circuits: G = R/|Z|², B = −X/|Z|². Returns conductance, susceptance, magnitude and phase angle. Supports any subset of R/L/C.

Compute the total, sensible, and latent capacity of an air-handling-unit (AHU) coil from the entering/leaving air state and the dry-air mass flow ṁ_da. Total capacity Qt = ṁ_da·(h1 − h2); sensible capacity Qs = ṁ_da·cp_ma·(T1 − T2) with cp_ma ≈ 1.006 + 1.86·W [kJ/(kg da·K)]; latent capacity Ql = Qt − Qs; Sensible Heat Ratio SHR = Qs / Qt. Each state is described by dry-bulb T plus one humidity input (relative humidity φ, or humidity ratio W); W is derived from the Magnus saturation fit when RH is supplied, and enthalpy h = 1.006·T + W·(2501 + 1.86·T) [kJ/kg da]. Signed result — works for cooling or heating coils.

Solve math problems from images using AI vision models with step-by-step explanations

Compute the air change rate (ACH / n) of a room from the outdoor supply airflow Q and the room volume V: n = Q/V (1/h). Three modes: solve ACH (given Q and V), solve airflow (given n and V), or solve volume (given n and Q). Flow in m³/s/m³/h/CFM, volume in m³/ft³/L. Also reports the well-mixed single-zone purge time to reach a target residual fraction ε (default 1%): t = −ln(ε)/n hours.

Convert between different angle units (degrees, radians, gradians, minutes, seconds, etc.)

Run one-way ANOVA across multiple groups and inspect sums of squares, F statistic, and p-value

Calculate antilogarithms for any valid base and optionally verify the result by applying the logarithm again

Convert arcminutes to degrees with configurable decimal precision

Convert arcseconds to degrees with configurable decimal precision

Convert between different area units (square meters, square feet, acres, hectares, etc.)

Calculate the nth term, first terms, and finite sum of an arithmetic sequence

Convert standard atmospheres to kilopascals with configurable decimal precision

Compare arithmetic, geometric, and harmonic averages for a numeric dataset in one place

Convert bar to kilopascals with configurable decimal precision

Convert bar to pounds per square inch with configurable decimal precision

Convert numbers and text between any radix from 2 to 36, with custom alphabets and presets for Base58, Base62, and Crockford Base32.

Perform basic arithmetic calculations with support for multiple operations

Calculate posterior probability P(A given B) using prior, likelihood, and false-positive rate