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Statistics Calculator with quartiles

Paste up to 500 numbers and get the common summary statistics at once, computed with exact fractions until the final decimal.

Try:

Answer

Enter your numbers or pick an example — the answer and the steps appear here instantly.

One list, a full summary

  • Center

    Mean, median and every mode. When no value repeats, the calculator says so instead of naming a mode.

  • Spread

    Minimum, maximum, range, quartiles Q1 and Q3, and the interquartile range between them.

  • Variance and standard deviation

    Both the sample (n − 1) and population (N) versions side by side, so you can use whichever your problem needs.

  • Flexible input

    Separate values with commas, spaces or new lines. Decimals and fractions such as 3/4 are fine, up to 500 values.

  • Exact arithmetic

    Sums and means are kept as exact fractions internally, so results are rounded only at the very end, where ≈ marks them.

  • Count and sum

    The count and the sum of the list are shown too, which makes it easy to confirm the mean by hand.

How to find the median and quartiles by hand

Sort the data first. The median is the middle value, and with an even count it is the mean of the two middle values. For 4, 8, 15, 16, 23, 42 there are six values, so the median is (15 + 16)/2 = 15.5.

Quartiles split each half again. With the median-of-halves method this calculator uses, Q1 is the median of the lower half and Q3 the median of the upper half; when the count is odd, the middle value belongs to neither half. Here the halves are 4, 8, 15 and 16, 23, 42, so Q1 = 8, Q3 = 23 and the IQR is 23 − 8 = 15.

Textbooks and software do not all agree on quartiles. Spreadsheets and several statistics packages interpolate between values, and some courses include the median in both halves, so the same list can give slightly different Q1 and Q3 elsewhere. Check which method your course expects.

The mean of the same list is 108/6 = 18, noticeably higher than the median, because the single large value 42 pulls it up. When a data set is skewed like this, the median often describes a typical value better.

Using the statistics calculator

  1. Paste your data

    A column copied from a spreadsheet or numbers from a worksheet both work, one per line or separated by commas.

  2. Calculate

    All statistics appear together as labeled values with a numbered outline.

  3. Pick the right spread

    Use the sample figures for data drawn from a larger group and the population figures when you have every member.

  4. Go further

    Send the list to the AI Math Solver for an explanation, or ask a follow-up in AI Chat about what the IQR says.

Frequently asked questions

The two use different quartile methods. This calculator takes the median of each half and leaves out the middle value for odd counts, while Excel's QUARTILE functions interpolate. Neither is wrong; use the method your course specifies.

Every value that ties for the highest frequency is listed. If each number appears just once, you see a note that no value repeats.

Use the sample version (dividing by n − 1) when your numbers are a subset of a larger group you want to describe. Use the population version (dividing by N) when the list contains every member, such as all students in one class.

You can enter up to 500 values per calculation, as whole numbers, decimals or fractions.

Yes, with no sign-up: the statistics are computed in your browser, and your data stays on your device unless you ask for an AI explanation. That explanation is the only metered part, included in the Pro plans* (*fair use: up to 300 runs a day across the writing, study and code tools) or 2 credits without a plan, and signed-out visitors can preview its start.

Use it to check your hand calculations and learn the vocabulary. The AI explanation can contain mistakes, and your course's rules decide whether AI tools are allowed on graded work.

More statistics tools

Summarize a data set

Mean, median, mode, quartiles and spread from one pasted list.

Analyze my data
  • Sample and population figures
  • Up to 500 values
  • Exact until the last step