How to Read the Periodic Table — Free Interactive Tool (2026)
By Rui Barreira · Last updated: 18 June 2026
Explore all 118 elements with the free interactive Brevio Periodic Table — click any element to see its atomic number, mass, electron configuration, group, period, and category.
How to Use the Periodic Table Tool
- The table displays all 118 elements color-coded by category (alkali metals, noble gases, transition metals, etc.).
- Click any element tile to expand a detail panel showing its full properties.
- Click the same element again to dismiss the panel.
- Use the color legend at the bottom to identify element categories at a glance.
- Lanthanides (La–Lu) and actinides (Ac–Lr) appear in the two separated rows below the main table.
How to Read the Periodic Table
Elements are arranged by increasing atomic number (Z) — the number of protons in the nucleus. Each row is called a period; elements in the same period have the same number of electron shells. Each column is a group; elements in the same group have similar chemical properties because they share the same number of valence electrons. Group 1 (alkali metals) have 1 valence electron; Group 17 (halogens) have 7; Group 18 (noble gases) have a full outer shell.
Understanding Element Categories
The periodic table groups elements into categories based on their properties. Metals (alkali, alkaline earth, transition, post-transition) conduct electricity and are typically shiny solids. Nonmetals are poor conductors and include gases like oxygen and nitrogen. Metalloids like silicon sit on the border and have properties of both. Noble gases are chemically inert — they have full outer electron shells and rarely form compounds.
Frequently Asked Questions
- How many elements are in the periodic table?
- 118 confirmed elements as of 2024. Elements 1–94 occur naturally; 95–118 are synthetic.
- What is atomic mass?
- Atomic mass (in atomic mass units, u) is the weighted average mass of an element's naturally occurring isotopes. Values in parentheses (e.g., (98)) indicate the most stable isotope's mass for elements with no stable isotopes.
- What is electron configuration?
- Electron configuration describes how electrons are distributed across energy levels and subshells. Shorthand notation uses a noble gas core in brackets (e.g., [Ne]) to represent the inner electrons.
- Is this tool free?
- Yes, completely free with no sign-up required.
Frequently Asked Questions
- How many elements are in the periodic table?
- 118 confirmed elements as of 2024. Elements 1–94 occur naturally; 95–118 are synthetic.
- What is atomic mass?
- Atomic mass (in atomic mass units, u) is the weighted average mass of an element's naturally occurring isotopes. Values in parentheses indicate the most stable isotope's mass for elements with no stable isotopes.
- What is electron configuration?
- Electron configuration describes how electrons are distributed across energy levels and subshells. Shorthand notation uses a noble gas core in brackets to represent the inner electrons.
- Is this tool free?
- Yes, completely free with no sign-up required.