A graphing calculator that runs in your browser
Zeta is a free simulator of a graphing calculator. It runs entirely on your own device — there is no account, no upload, and nothing you type is sent to a server. Point a phone, tablet or laptop at this page and you have the calculator, including the parts that usually cost money: exact symbolic arithmetic, graphing, and a real Python interpreter.
What you can do with it
- Calculation — exact arithmetic that keeps fractions, surds and π intact instead of rounding them to decimals.
- Functions — plot several functions at once, then trace them and read off zeros, intersections, extrema and integrals.
- Equations — solve equations and linear systems, exactly where an exact answer exists.
- Statistics — enter data and get the usual summaries, histograms and box plots.
- Regression — fit linear, quadratic, exponential, logarithmic, power and logistic models to a scatter plot.
- Probability — normal, binomial, Poisson, geometric, Student, χ² and Fisher distributions.
- Sequences — explicit and recurrence-defined sequences, as tables or graphs.
- Python — a MicroPython interpreter with the
math,turtle,random,cmathandmatplotlib-style plotting modules.
Your work is saved
Unlike the official web simulator, this one remembers what you were doing. Functions, sequences, statistics data, variables and Python scripts are stored in your browser and are still there when you come back. Nothing leaves your device. You can export the whole calculator state to a file and import it on another machine, and the Reset button returns it to factory condition.
Keyboard shortcuts
On a laptop you can type instead of clicking. The numeric keypad works as you would expect, and so do layouts where the number row does not produce digits.
| Key | Does |
|---|---|
0–9 . + − * / ( ) ^ | The matching calculator key |
Enter | EXE — evaluate |
Esc | Back |
Backspace | Delete |
Arrow keys | Move the cursor / selection |
Space | OK — confirm |
Home | Home — the applications screen |
Tab | Toolbox |
Shift / Alt | shift / alpha |
x v p q i | x,n,t · var · π · √ · imaginary i |
s c l e a | sin · cos · ln · eˣ · ans |
Sharing a Python script by link
Add a script to the URL and it is loaded into the calculator when the page opens — handy for handing a worked example to a class:
https://calculator.chameleon-solutions.com/?script=demo&code=print("hello")Use code64 with a base64url-encoded body instead of code for longer scripts.
Installing it on a phone
Use your browser’s Add to Home Screen option and the calculator opens full-screen, without browser chrome. It still needs a connection the first time it loads.
Is it free?
Yes, and it always will be. The calculator firmware it is built on is licensed for non-commercial use only, so this site carries no advertising, no paywall and no sponsorship — adding any of those would breach the licence.
Credits and licence
Runs a modified build of NumWorks Epsilon 15.5.0, © NumWorks SAS, used under CC BY-NC-SA 4.0. The engine was modified to let the calculator’s storage be saved and restored; the keypad and surrounding interface are original work. This site is not affiliated with, endorsed by, or sponsored by NumWorks SAS, and NumWorks is a registered trademark of NumWorks SAS.