Scientific calculator
Free scientific calculator for expressions, powers, roots and trigonometry. Choose degrees or radians, check worked examples and review calculation rules.
By Calcr · Updated
Scientific calculator: Enter a scientific expression
Use parentheses to make grouping explicit, then calculate. The calculator supports arithmetic, powers, square roots, sin, cos, tan, base-10 log, natural log, pi and e. Select DEG for degrees or RAD for radians before using trigonometry. Your recent calculations stay in the current session.
Order of operations and examples
Parentheses are evaluated first. Powers precede multiplication and division; addition and subtraction follow. Use an explicit multiplication sign when entering a product.
- Grouping: 18 / (2 * 3) = 3. Without those parentheses, 18 / 2 * 3 = 27.
- Angles: in DEG mode, sin(30) = 0.5. In RAD mode, sin(pi / 6) = 0.5.
- Percent: 240 * 15% = 36. The percent sign means divide by 100, so 200 + 10% = 200.1. To increase 200 by 10%, enter 200 * (1 + 10%).
Precision and limits
Calculations use decimal BigNumber arithmetic with 32 significant digits internally and show up to 12 significant digits. A displayed decimal can be rounded. Division by zero, real square roots of negative numbers and unsupported expressions return an error. Expressions are limited to 512 characters and a short execution budget. This is a numerical calculator, not a symbolic algebra system.
When to use this scientific calculator
Use this free scientific calculator when the task can be written as a numerical expression and you want to inspect the steps yourself. It suits checking a homework calculation, evaluating a formula with known measurements, converting a percentage into a multiplier, or comparing two numerical scenarios. Write the expression on paper first if the relationship is unclear. The calculator can evaluate a formula, but it cannot decide which formula describes your problem.
Keep units consistent before entering numbers. For a rectangle measuring 2 metres by 35 centimetres, convert 35 centimetres to 0.35 metres before calculating 2 * 0.35. The numerical answer is 0.7 and its area unit is square metres. Entering 2 * 35 instead produces 70, which describes neither the intended square metres nor a valid conversion. Units are part of your setup even though the expression field contains numbers.
Use another tool when the output needs a different kind of reasoning. The fraction calculator preserves a rational result as a fraction. The grade calculator checks assessment weights. A calendar tool knows that February and March have different lengths. This calculator does not solve equations with unknown variables, prove identities, manipulate matrices or provide complex-number answers. A rejected expression can indicate an unsupported operation rather than a mathematical impossibility.
Example: checking a geometric formula
Suppose a right triangle has perpendicular sides of 9 and 12 in the same unit. The hypotenuse is sqrt(9^2 + 12^2). Squaring the inputs gives 81 and 144, adding gives 225, and taking the square root gives 15. The parentheses keep the entire sum inside the root. Entering sqrt(9^2) + 12^2 asks a different question and gives 153. Both expressions are numerically valid, so grouping is the check that catches the mistake.
This example assumes a right angle; the same expression does not calculate an arbitrary triangle's third side. Keep the result in the original length unit. If the sides are measurements rounded to the nearest centimetre, a display showing many digits would not make the measurement more precise. The tool reports arithmetic precision, while the original observations determine useful reporting precision.
Example: growth with repeated percentage changes
An illustrative quantity starts at 500, increases by 8%, then decreases by 5%. Enter 500 * 1.08 * 0.95 to obtain 513. The first step gives 540, and the second step removes 27. The net change is 13, or 2.6% of the starting quantity. Subtracting 5 from 8 and calling the outcome a 3% increase would ignore that the second change uses 540 as its base.
To check the net percentage in one expression, enter (513 - 500) / 500 * 100. This produces 2.6. Keep the growth factors unrounded until the final step, especially when repeating them many times. This is a numerical scenario, not a promise about investment performance or any real-world rate.
Before sharing a result, copy the expression, the angle mode and the final answer together. An answer such as 0.5 alone does not show whether it came from sin(30) in degrees or another expression. For a longer calculation, check one intermediate value at a time and compare the rough size with what you expected. If a result looks implausible, inspect the inputs and grouping before adding more decimal places.
An error does not leave the last successful answer as the result of the new expression. Correct the input and calculate again. For example, sqrt(-1) is outside this real-number calculator, while sqrt(1) returns 1. If a copied formula contains a multiplication symbol or a superscript from another document, rewrite it using the supported keypad or plain expression syntax before retrying. Check that every opening parenthesis has a closing partner. For the underlying arithmetic and function conventions, see the openly available OpenStax Algebra and Trigonometry reference.
FAQ
Why does sin give an unexpected result?
Check DEG/RAD first. The number 30 means different angles in the two modes.
What is the difference between log and ln?
Log uses base 10; ln uses base e. For example, log(100) = 2 and ln(e) = 1.
Is a rounded result exact?
Not necessarily. Keep full intermediate precision and round only the final answer when possible. Use the fraction calculator for exact rational arithmetic.
Why does a negative number raised to a power need parentheses?
Parentheses state whether the negative sign belongs to the base. The expression (-3)^2 squares negative three and gives 9. The expression -(3^2) negates a square and gives -9. When a formula contains a negative input, group that input explicitly so the expression records your intention. This matters even when you can perform the small example mentally; in a long formula the same sign mistake is harder to see.
Can I recover my calculations on another device?
The recent-history panel belongs to the current browser session. It is useful for reviewing nearby calculations, but it is not an account-backed notebook or a synced record. Copy important expressions and results into your own notes before leaving the session. Avoid including personal or confidential measurements when you only need to demonstrate how an expression works.