List of Online Calculators for Math, Physics, Earth and Other Curiosities

I've gone through my bookmarks and found some interesting aka helpful online tools.
Please report broken links to a moderator. Additional ones should be added here, so again please contact a moderator.

Links checked: 06/20/23
Latest Update: 12/19/23 (Omni Calculator)

Time
https://greenwichmeantime.com/

Calendar
https://www.timeanddate.com/calendar/?year=2022&country=1

Duration
https://www.timeanddate.com/date/duration.html

Location And Distance of Orbits
https://www.n2yo.com/ (ISS)
https://in-the-sky.org/satmap_worldmap.php (Satellites)
http://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html (Solar System)

Continental Drift
https://dinosaurpictures.org/ancient-earth#220

Units Calculator
http://www.onlineconversion.com/
https://unitconverter.net/

Physical Constants
https://physics.nist.gov/cuu/Constants/index.html

Physical Computations of all kinds
https://www.omnicalculator.com/physics

Engineering Toolbox
https://www.engineeringtoolbox.com/

Barometric Formula Calculator
http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/barfor.html

Temperature at Altitude Calculator
https://www.omnicalculator.com/physics/altitude-temperature

Routh Hurwitz Criterion Calculator (Control Theory)
https://www.muchen.ca/RHCalc/

Wolfram Alpha For Computing Answers And Providing Knowledge
https://www.wolframalpha.com/

Omni Calculator (all kinds of everyday needs, e.g. wind turbines or build-or-buy)
https://www.omnicalculator.com/ecology/wind-turbine

Formula Calculator With Assisted Input (Mathway / Symbolab)
https://www.mathway.com/Algebra
https://www.symbolab.com/solver

Various Universal Calculators
https://www.fxsolver.com/solve/
https://pari.math.u-bordeaux.fr/gp.html (number theory heavy)

Random Numbers And String Generator
https://www.random.org/
https://libraryofbabel.info/book.cgi?0-w1-s1-v01:1

Chinese Remainder Theorem
https://www.dcode.fr/chinese-remainder

Euler's Totient Calculator
http://www.javascripter.net/math/calculators/eulertotientfunction.htm

RSA Calculator
https://www.cs.drexel.edu/~jpopyack/IntroCS/HW/RSAWorksheet.html
https://www.cs.drexel.edu/~jpopyack...yptography/RSA_Express_EncryptDecrypt_v2.html

Runge-Kutta Algorithm
https://planetcalc.com/8400/

SIR Calculator
http://math.colgate.edu/~wweckesser/solver/DiseaseSIR.shtml

Lotka-Volterra Calculator
https://fusion809.github.io/LotkaVolterra/

Derivative Calculator
https://www.derivative-calculator.net/

Integral Calculator
https://www.integral-calculator.com/

Euler Method Calculator y'=f(x,y)
https://planetcalc.com/8389/
https://keisan.casio.com/exec/system/1392171850

Matrix Calculator
https://www.symbolab.com/solver/matrix-calculator
https://www.emathhelp.net/calculators/linear-algebra/gram-schmidt-calculator/

Extended Euclidean Algorithm (Bézout's Lemma)
https://www.extendedeuclideanalgorithm.com/calculator.php

Symbolic Calculations in Algebra
http://magma.maths.usyd.edu.au/magma/documentation/

Encryption
https://cryptii.com/pipes/caesar-cipher

##\chi^2## -Test
http://quantpsy.org/chisq/chisq.htm

Regression Calculator (best fit)
https://elsenaju.eu/Calculator/online-curve-fit.htm

Confidence Interval Calculator
http://statpages.info/confint.html

Sample Size Calculator
https://www.calculator.net/sample-size-calculator.html

Poisson Distribution Calculator
https://stattrek.com/online-calculator/poisson.aspx

Normal Distribution Calculator
https://stattrek.com/online-calculator/normal.aspx
http://davidmlane.com/hyperstat/z_table.html

Statistics
https://www.socscistatistics.com/tests/regression/default.aspx
https://www.danielsoper.com/statcalc/default.aspx

Binomial Probability Calculator
https://stattrek.com/online-calculator/binomial.aspx

Primality
https://www.dcode.fr/primality-test
https://www.dcode.fr/prime-number-pi-count

Factorization
https://www.alpertron.com.ar/ECM.HTM

Number Base Converter
https://www.rapidtables.com/convert/number/base-converter.html

Geometry Calculator (e.g. icosahedron, triangle)
https://rechneronline.de/pi/icosahedron.php
https://rechneronline.de/pi/triangle.php

Graphics
https://academo.org/demos/3d-surface-plotter/
https://www.math3d.org/
https://www.desmos.com/calculator?lang=en
https://www.geogebra.org/

Visualization of Complex Functions
https://complex-analysis.com/content/analytic_landscapes.html

File Format Converter (chg ext)
https://cloudconvert.com/

Character Counter
https://www.lettercount.com/

Morse Code Converter and more
https://onlinetexttools.com/convert-text-to-morse
https://www.browserling.com/tools/text-to-morse

Upside Down Characters
https://text-symbols.com/upside-down/

Tables to LaTeX
https://www.tablesgenerator.com/

LaTeX previewer
http://mathb.in/
https://quicklatex.com/

Image Resizer
https://picresize.com/

GIF Maker
https://ezgif.com/

Circuit Simulator
http://falstad.com/circuit/

Tone Generator
https://onlinetonegenerator.com/
https://www.szynalski.com/tone-generator/

Cosmology
https://light-cone-calc.github.io/
https://astro.uchicago.edu/~gnedin/cc/
https://astro.ucla.edu/~wright/ACC.html
https://janus.astro.umd.edu/orbits/ssbuild.html

NASA Data of Solar System
https://ssd.jpl.nasa.gov/?site_map

Einstein Velocity Addition
http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/einvel2.html

Satellites
https://www.heavens-above.com/
http://www.satview.org/now.php

Orbital Velocity Calculator
https://www.omnicalculator.com/physics/orbital-velocity

Escape Velocity
https://keisan.casio.com/exec/system/1360310353

Your Weight on Other Planets
https://www.exploratorium.edu/explore/solar-system/weight

Density At Altitude
https://wahiduddin.net/calc/calc_da.htm

Particle (Physics) Data Group
https://pdg.lbl.gov/

Hawking Radiation Calculator
https://www.vttoth.com/CMS/physics-notes/311-hawking-radiation-calculator

Blackbody Radiation Calculator
https://www.spectralcalc.com/blackbody_calculator/blackbody.php

Color Calculator
https://rechneronline.de/spectrum/

Speed Of Sound
http://www.sengpielaudio.com/calculator-speedsound.htm

Chemical Elements
https://www.nndc.bnl.gov/nudat2/

Chemistry / AI / Finance / Linear Algebra / etc.
http://www.gregthatcher.com/

Mechanical Engineering
https://calcresource.com/index.html

Calculate Depth of a Well by Stone (metric)
https://rechneronline.de/physics/stone-well.php

US-American Drainage Divides
https://river-runner.samlearner.com/ (nice interactive graphic and video)

Lift to Drag Ratio in Aerodynamics
https://www.fxsolver.com/browse/?q=Lift+to+drag&cat=138

Hovercraft Lift
https://hoverhawk.com/lcalc.html

Hieroglyphs (no guarantee)
https://lingojam.com/HieroglyphicsTranslator

Non English Calculators
https://www.calculat.org/de/flacheninhalt-umfang/polygon.html (German; basics)
http://elsenaju.info/ (German; esp.: vector fields of differential equations)
http://www.arndt-bruenner.de/mathe/mathekurse.htm (German; esp.: Java script for digital clock)
https://www.leifiphysik.de/astronomie/planetensystem/versuche/planetenbewegungen-simulation (German; Solar System)
http://kuffner-sternwarte.at/astronomie/sonnensystem-simulator/index.php (German; Solar System)
https://www.periodensystem-online.de/index.php (German; periodic table)
https://www.fersch.de/ (German; collections of formulas, mathematics and physics)
https://de.numberempire.com/ (German; WA light)