A high precision scientific calculator with full support for physical units.

• Web version
• Terminal version

• Evaluate mathematical expressions:

  1920/16*9
  2^32
  sqrt(1.4^2 + 1.5^2) * cos(pi/3)^2
  

  • Operators: addition (+), subtraction (-), multiplication (*, ·, ×), division (/, ÷, per), exponentiation (^, **). Full list: see Reference below.

  • Mathematical functions: acos, acosh, asin, asinh, atan, atanh, ceil, cos, cosh, exp, floor, fromCelsius, fromFahrenheit, gamma, ln, log, log10, round, sin, sinh, sqrt, tan, tanh, toCelsius, toFahrenheit.

  • High-precision numeric type with 30 significant digits that can handle very large (or small) exponents like 10^(10^10).

  • Exponential notation: 6.022e23.

• Physical units: parsing and handling, including metric prefixes:

  2 min + 30 s
  40 kg * 9.8 m/s^2 * 150 cm
  sin(30°)
  

  • Supported units: see Reference section below.

  • Implicit conversions: 15 km/h * 30 min evaluates to 7.5 km.

  • Useful error messages:

    > 2 watts + 4 newton meter
    
    Unification error:
      Cannot convert unit N·m (base units: kg·m²·s⁻²)
                  to unit W (base units: kg·m²·s⁻³)
    

• Explicit unit conversions: the -> conversion operator (aliases: →, ➞, to):

  60 mph -> m/s
  500 km/day -> km/h
  1 mrad -> degree
  52 weeks -> days
  5 in + 2 ft -> cm
  atan(30 cm / 2 m) -> degree
  6 Mbit/s * 1.5 h -> GB
  

• Variable assignments:

  Example: mass of the earth

  r = 6000km
  vol = 4/3 * pi * r^3
  density = 5 g/cm^3
  vol * density -> kg
  

  Example: oscillation period of a pendulum

  len = 20 cm
  2pi*sqrt(len/g0) -> ms
  

  • Predefined constants (type list to see them all): speed of light (c), Planck's constant (h_bar), electron mass (electronMass), elementary charge (elementaryCharge), magnetic constant (µ0), electric constant (eps0), Bohr magneton (µ_B), Avogadro's constant (N_A), Boltzmann constant (k_B), gravitational acceleration (g0), ...

  • Last result: you can use ans (answer) to refer to the result of the last calculation.

• Unicode support:

  λ = 2 × 300 µm
  ν = c/λ → GHz
  

• And more: tab completion, command history (arrow keys, Ctrl+R), pretty printing, syntax highlighting, ...

• Operators (ordered by precedence: high to low)

  Operator	Syntax
  factorial	!
  square, cube, ...	², ³, ⁻¹, ...
  exponentiation	^, **
  multiplication (implicit)	whitespace
  modulo	%
  division	/, ÷, per
  multiplication (explicit)	*, ·, ×
  subtraction	-
  addition	+
  unit conversion	->, →, ➞, to
  assignment	=

  Note that implicit multiplication has a higher precedence than division, i.e. 50 cm / 2 m will be parsed as 50 cm / (2 m).

• Commands

  Command	Syntax
  help text	help, ?
  list of variables	list, ls, ll
  reset environment	reset
  clear screen	clear, cls
  quit (CLI)	quit, exit

• Supported units (remember that you can use tab completion).

  All SI-accepted units support metric prefixes. In addition, binary prefixes (MiB, GiB, ...) are also supported.

  Unit	Syntax
  Ampere	amperes, ampere, A
  Ångström	angstrom, Å
  Astronomical unit	AU
  Atmosphere	atm
  Bar	bar
  Barn	barn
  Becquerel	becquerel, Bq
  Bel	bel
  Bits per second	bps
  Bit	bits, bit
  British thermal unit	BTU
  Byte	Bytes, bytes, Byte, byte, B, Octets, octets, Octet, octet
  Calorie	calories, calorie, cal
  Candela	candela, cd
  Coulomb	coulomb, C
  Cup	cups, cup
  Day	days, day, d
  Degree	degrees, degree, deg, °
  Electronvolt	electronvolt, eV
  Farad	farad, F
  Fortnight	fortnights, fortnight
  Fluid ounce	fluidounces, fluidounce, floz
  Furlong	furlongs, furlong
  Foot	feet, foot, ft
  Gallon	gallons, gallon, gal
  Gauss	gauss
  Gram	grams, gram, grammes, gramme, g
  Gray	gray, Gy
  Hectare	hectare, ha
  Henry	henry, H
  Hertz	hertz, Hz
  Hogshead	hogsheads, hogshead
  Hour	hours, hour, h
  Inch	inches, inch, in
  Joule	joules, joule, J
  Katal	katal, kat
  Kelvin	kelvin, K
  Light-year	lightyears, lightyear, ly
  Liter	liters, liter, litres, litre, L, l
  Lumen	lumen, lm
  Lux	lux, lx
  Meter	meters, meter, metres, metre, m
  Miles per hour	mph
  Mile	miles, mile
  Millimeter of mercury	mmHg
  Minute	minutes, minute, min
  Mole	mole, mol
  Month	months, month
  Newton	newton, N
  Ohm	ohms, ohm, Ω
  Ounce	ounces, ounce, oz
  Parsec	parsecs, parsec, pc
  Pascal	pascal, Pa
  Pint	pints, pint
  Pound	pounds, pound, lb
  Psi	psi
  RPM	RPM, rpm
  Radian	radians, radian, rad
  Rod	rods, rod
  Second	seconds, second, sec, s
  Siemens	siemens, S
  Sievert	sievert, Sv
  Tablespoon	tablespoons, tablespoon, tbsp
  Teaspoon	teaspoons, teaspoon, tsp
  Tesla	tesla, T
  Tonne	tonnes, tonne, tons, ton, t
  Volt	volts, volt, V
  Watt	watts, watt, W
  Watt-hour	Wh
  Weber	weber, Wb
  Week	weeks, week
  Yard	yards, yard, yd
  Year	years, year

In addition to the web interface, there is also a command line version which can by installed via npm:

npm install -g insect

For Arch Linux, there is a package on AUR:

yaourt -S insect

For Fedora, there is a copr repository:

sudo dnf copr enable fnux/insect
sudo dnf install insect

For macOS, there is a Homebrew package:

brew install insect

Insect is written in PureScript (see Getting Started guide). You can install all dependencies and build the whole project by running:

bower install
npm install
pulp -w browserify --skip-entry-point -m Insect --standalone Insect -O -t insect.js

Insect comes with a comprehensive set of unit tests. You can run them by calling

pulp test