Ion Calculator. An ion is an atom that has gained or lost electrons, giving it a positive or negative electrical charge — this calculator works out that charge from your atom's electron count. Enter the number of protons and number of electrons into the Ion Calculator to get the ion charge, charge type (cation or anion), charge magnitude, and electrons gained or lost. You can also add an optional element symbol for easy reference. Also try the Total Activity — Neutron Activation.
Ion charge is calculated by subtracting the number of electrons from the number of protons. If protons > electrons, the ion is positive (cation). If electrons > protons, the ion is negative (anion). See also our find Remaining Activity with Nuclear Decay Chain Calculator.
A cation is a positively charged ion (has fewer electrons than protons), while an anion is a negatively charged ion (has more electrons than protons). The charge magnitude determines how many electrons were gained or lost.
Yes, when an atom has equal numbers of protons and electrons, it has zero net charge and is electrically neutral. This is the normal state for most atoms before they form ions.
The maximum positive charge is limited by the number of electrons an atom can lose (usually valence electrons), while maximum negative charge depends on how many electrons the atom can accommodate in its outer shells.
Ion charge determines how ions interact with each other. Opposite charges attract to form ionic bonds, while like charges repel. The magnitude of charge affects the strength of these interactions.
Elements with multiple valence states (like transition metals) can lose different numbers of electrons, forming ions with different charges. For example, iron can form Fe²⁺ or Fe³⁺ ions. You might also find our Radioactive Decay Calculator (Nuclear) useful.