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Scientific Calculator

Scientific functions and physical constants

Checked against 3,700+ answers

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Fractions and roots shown like a textbook, exact answers like √2/2, plus statistics, equations, matrices and base-n.

  • √2/2exact answers
  • 23physical constants (CODATA 2022)
  • 3,700+answers checked in tests

Try it here

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Answers come out exact, like √2/2, and S⇔D switches to the decimal.

On a keyboard, / makes a fraction and Enter means =

  1. Start with an exampleOn the empty screen, tap ⅓+¼ under ‘Try’ and it is worked out at once: 7/12.
  2. Fractions with □/□Press ‘□/□’ for a top and bottom box, and 1 □/□ 3 ▶ + 1 □/□ 6 = gives 1/2.
  3. More with SHIFTThe orange label above a key works after ‘SHIFT’, so SHIFT sin 0.5 = gives 30.
  4. Reuse from historyUp to 40 calculations stay in ‘History’ in this browser, and tapping one brings the expression back.

It can also

What it checks and discloses

Results are compared automatically with about 3,700 answers computed separately in Python (sympy, mpmath, scipy and numpy), and the physical constants were checked digit by digit against the NIST table.

6÷2(1+2) gives 1, following the order in Casio’s manual

Rules and sources

Exact values
Fractions, roots and π are kept exact instead of being turned into decimals, so 0.1+0.2−0.3 gives 0; anything with no exact form uses ordinary decimals (about 16 significant digits).About this calculator
Order of operations
Brackets, functions, powers (left to right), products written without a × sign, then × ÷ and + −. So −2² is −4.Calculation priority table in the Casio fx-570ES PLUS / fx-991ES PLUS manual
Normal display
Up to 10 significant digits, with very large or very small numbers in scientific notation; rounding is half up.About this calculator
Integrals and derivatives
The ∫ and d/dx keys give numeric values for definite integrals and for a derivative at a point; integrals keep splitting the interval until the error estimate is small.About this calculator (Gauss–Kronrod 7-15, Ridders’ method)
Physical constants
Constants such as the speed of light and the Planck constant are shown with units and marked when the SI value is exact.NIST Fundamental Physical Constants, CODATA 2022

There is a small graph under the table of values, but it is not a graphing calculator.

More rules in About Scientific Calculator

5 guides

  1. 6÷2(1+2) = 1 or 9? Order of operations on a calculator
  2. σ vs s: population or sample standard deviation?
  3. Degrees vs radians: why sin 30 gives −0.988 on your calculator
  4. Solving quadratic and simultaneous equations
  5. Permutations vs combinations: nPr and nCr explained

All guides

Fixed the keypad shifting as you type and nested brackets in history

  1. Fixed the keypad jumping up and down while you type, which made taps land on the wrong key.

  2. The first screen has less text now: three tips are shown and the rest sit under ‘More tips’.

  3. Expressions with nested brackets, like abs(sin(x)), now come back correctly from history.

  4. The graph under the table of values is now drawn from more than 200 points, so curves come out smooth.

  5. Launched with three ‘Try’ examples and a ‘Keys’ chart of what every key does.

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