Finance
Calculate capital gains tax on investments and asset sales
capital-gains-taxFinance
Convert between cryptocurrencies and fiat currencies with real-time rates
crypto-converterMath & Numbers
Calculate the digital root of numbers. The digital root is the recursive sum of digits until a single digit is obtained.
digital-root-calculatorMath & Numbers
Deduplicated, lexicographic permutations / combinations / subsets of up to 12 items with exact multiset counts; display capped at 200 entries.
combinatorial-generationMath & Numbers
Numeric (f*g)(t) = ∫ f(τ)g(t−τ)dτ by composite Simpson, in causal or direct-window mode, at up to 8 output points.
convolution-integral-calculatorFinance
Explore how contributions, compounding, fees, and inflation shape investment growth year by year.
compound-interest-contribution-timeline-tutorMath & Numbers
Estimate the saturated condensing temperature (T_cond) and evaporating temperature (T_evap) of a refrigeration circuit. Three modes: (1) from coil approach — T_cond = T_ambient + condenser ΔT approach, T_evap = T_medium − evaporator ΔT approach; (2) from measured saturated pressures — given P_cond and P_evap for a known refrigerant (R-22 / R-134a / R-410A), invert the Antoine fit; (3) from subcooling & superheat — T_cond = T_liquid − SC, T_evap = T_suction − SH. Temperature in °C/K/°F; pressure in bar/MPa/kPa/PSI absolute or gauge (atmospheric default 1.01325 bar). Results reported in °C.
condensing-temperature-calculatorMath & Numbers
Estimate the cooling load of a room by the simplified ASHRAE steady-state method. Transmission sensible load Q_trans = Σ(A_i·U_i·ΔT) over envelope surfaces entered one per line as 'area,U' (U in W/(m²·K)). Infiltration/ventilation sensible Q_s = 1.23·ACH·V·ΔT and latent Q_l = 3010·ACH·V·ΔW (W), where ΔW is the indoor-outdoor humidity-ratio difference derived from dry-bulb temperature and relative humidity via the Magnus saturation fit. Total cooling load = total sensible + total latent. Temperature in °C/K/°F (only differences matter), area in m²/ft².
cooling-load-calculatorMath & Numbers
Compute the Coefficient of Performance (COP) of a chiller / heat pump: COP = Q_c / W, where Q_c is the cooling capacity and W the work input (both in consistent power units; COP is dimensionless). Three modes: solve COP (given Q_c and W), solve cooling capacity (given COP and W), or solve input power (given COP and Q_c). Capacity in W/kW/BTU·h⁻¹/ton/kcal·h⁻¹, power in W/kW/hp; all converted to W internally.
cop-calculatorMath & Numbers
Calculate the Euler critical buckling load of an axially loaded column: P_cr = π²·E·I/(K·L)². Supports pinned-pinned (K=1), fixed-free (K=2), fixed-pinned (K=0.7), fixed-fixed (K=0.5). Returns effective length, radius of gyration, slenderness ratio λ, and critical stress σ_cr.
column-buckling-loadMath & Numbers
Convert between concrete strength notations: C grade ↔ cube strength fcu ↔ cylinder fck,cyl ↔ prism fck,prism ↔ design value fc. Ratios: fck,cyl = 0.8·fcu, fck,prism = 0.88·0.76·fcu, fc = fck,prism/1.4. Any one input produces all others.
concrete-strength-grade-converterMath & Numbers
Design a normal-weight concrete mix per ACI 211.1-91 absolute-volume method. Inputs: slump, nominal max aggregate size, air entrainment, water-cement ratio w/c, fineness modulus of sand, and dry-rodded coarse-aggregate density. Outputs the per-cubic-meter masses of cement, water, fine and coarse aggregate plus the mass ratio.
concrete-mix-design