Frequently Asked Questions
Everything you need to know about the Electron Configuration Calculator.
How does the electron configuration calculator work?
Pick an element by name, symbol, or atomic number, and it generates the configuration using the Aufbau filling order, correcting for known exceptions.
Is it free?
Completely free, no sign-up, downloads, or limits.
Does it handle ions?
Yes, enter a charge (e.g. 3 for Fe3+) and it computes the ion's configuration using the correct electron-removal order.
Does it give shorthand notation?
Yes, both full notation and noble-gas shorthand are shown.
What are the "exceptions" it mentions?
Elements like chromium and copper don't follow the naive Aufbau prediction because a half-filled or fully filled d-subshell is more stable โ the calculator applies the correct actual configuration and explains why.
Does it show an orbital diagram?
Yes, a box-notation diagram for the valence subshells showing Hund's rule.
Does it show valence electrons?
Yes, called out separately from the full configuration.
What if I enter an invalid element or impossible ion charge?
It's flagged clearly rather than producing a wrong configuration.
Is my data stored?
No; everything runs in your browser and isn't stored or sent anywhere.
Does it work on mobile?
Yes, fully responsive on all screen sizes.