Calculators that show the steps
Free GPA, statistics and chemistry calculators. Every answer shows the formula and how it was worked out, so you can check your homework.
All calculators
Formulas, worked out
Each calculator uses one of these. Here is each one with an example.

| Formula | Example |
|---|---|
| Molarity = moles ÷ liters | 0.50 mol NaCl in 2.0 L = 0.25 M |
| C₁V₁ = C₂V₂ | 100 mL of 0.1 M from 1.0 M stock: use 10 mL |
| s = √(Σ(x − x̄)² ÷ (n − 1)) | 2, 4, 4, 4, 5, 5, 7, 9: s = 2.14 |
| GPA = grade points ÷ credits | 178.9 points ÷ 55 credits = 3.25 |
| CI = x̄ ± t × s ÷ √n | x̄ = 72.5, s = 8.4, n = 30: 69.4 to 75.6 |
Common questions
How do you calculate cumulative GPA?
Multiply each GPA by its credits to get grade points, add the points together, then divide by the total credits. A 3.20 over 45 credits plus 34.9 points from 10 new credits gives (144 + 34.9) ÷ 55 = 3.25.
What is the difference between sample and population standard deviation?
Population standard deviation divides by n. Sample standard deviation divides by n − 1, which corrects for estimating from a sample. Use sample unless you have every value in the group. For 2, 4, 4, 4, 5, 5, 7, 9 the sample SD is 2.14 and the population SD is 2.00.
How do you calculate molarity?
Divide moles of solute by liters of solution. 0.50 mol of NaCl in 2.0 L of solution is 0.25 M.
Can I use these calculators for homework?
Yes, to check your answers. Each result shows the formula with your numbers in it, so you can compare it line by line with your own working. Most teachers still want you to show your own steps.