Free Interactive Periodic Table

Worked example

Type Fe into the search box ("Search by name, symbol, or number…") and press Enter. Iron and fermium stay bright and the other cells fade, because "Fermium" also starts with "fe", and Enter opens the first match, which is iron. The panel for Iron (Fe) shows Atomic number 26, Atomic mass 55.845, Category "Transition metal", Group 8, Period 4, Electron configuration "1s2 2s2 2p6 3s2 3p6 4s2 3d6", Noble-gas configuration "[Ar] 4s2 3d6", "Valence electrons (outer shell)" 2, "Melting point (°C)" 1538, "Boiling point (°C)" 2861, "Density (g/cm³)" 7.874 and "Discovered" "Known since antiquity". The "Electron shells" diagram is labelled 2 · 8 · 14 · 2. Choose "Density (g/cm³)" in the "Colour the table by" menu and the table turns into a heat map with the legend "Low 0.0000899" and "High 22.6". Elements with no density on file are grey, and the legend labels grey as "No data".

Which settings to use, and the limits

• Search by symbol, number or name, then filter by category. Exact symbols and atomic numbers match first, so Na and 11 both find sodium. Then come names that start with your text, and from three characters on, names that contain it: tun finds tungsten and neptunium. A few older names also work, such as aluminum, sulphur, cesium, natrium and wolfram. Matches stay bright and the rest fade. Enter opens the first match and Escape clears the box. The coloured category buttons under it work as filters too, and they combine with the search.
• Open the detail panel and copy what you need. Tap any element to open its panel with 16 fields and the "Electron shells" diagram. Tap a field to copy only that value, or press "Copy" at the bottom to copy the whole element as text. On a phone the panel is a bottom sheet that covers up to 55 percent of the screen height; close it with the × button. On wider screens it sits under the table, and the page scrolls to it only if it is off-screen, so look below the table if nothing seems to happen. Arrow keys move around the grid.
• Know what the values mean. Atomic mass is shown in square brackets, such as [98] for technetium and [294] for oganesson, for elements with no stable isotope. The bracket holds the mass number of the longest-lived isotope. A dash means there is no reliable value on file, mostly for the superheavy elements. Melting and boiling points are at 1 atmosphere, and density is at 20 °C (gases at 0 °C). "State at 20 °C" is worked out from those points, so only bromine and mercury read "Liquid". "Valence electrons (outer shell)" counts the outermost occupied shell, and palladium shows a dash. The page notes the values are for reference only.
• Colour the table by a property. "Colour the table by" offers Category, Atomic mass, Electronegativity (Pauling), Melting point (°C), Boiling point (°C), Density (g/cm³) and Atomic radius (pm). Low values are blue and high values are red, with the lowest and highest value in the legend. Density uses a log scale because it runs from 0.0000899 to 22.6. Not every element has a value: 99 of 118 have electronegativity, 102 melting point, 95 boiling point, 97 density and 91 radius. Those without are grey. Hover over a cell to see its value.
• Practise with the quiz and the ions list. "Quiz" opens flash cards drawn from all 118 elements. "Quiz type" offers Symbol → name, Name → symbol, Number → symbol and Symbol → number. Press "Show answer", then "I knew it" or "Missed it" to update "Score: 3 / 5", or "Skip" to move on without scoring. Closing the quiz and opening it again resets the score. "Common ions and charges" lists 29 ions, such as Fe2+ and Fe3+, and 16 polyatomic ions such as sulfate and nitrate, with the note that transition metals can form other charges too.
• Export the table as CSV, PNG or a printed page. "Download CSV" saves periodic-table.csv with one row for each of the 118 elements: Symbol, Name, then all 16 fields, using the current "Atomic mass" setting. "Download PNG" saves a 2339 × 1654 pixel picture, and "Print / save as PDF" puts it on one landscape A4 page. Tick or untick "Show number and mass on each cell in the print and PNG" first. The picture writes each mass as stored (55.845 for iron, 98 for technetium) and ignores the "2 decimals" setting.

Common problems and how to fix them

It says "No element matches “alumnium”." (with your own text)

The search compares your text with the symbol, the atomic number, the element's name and a few older names, so a spelling slip finds nothing. Matching inside a name needs three or more characters, and names are matched in English on this page. Try fewer letters, such as alum, which finds aluminium, or press Escape to clear the box. Formulas such as H2O are not searched.

The table is cut off and I have to swipe sideways.

On screens narrower than 640 px, "Fit table to screen" starts ticked and shows all 18 columns, with only the symbol in each cell. If it is unticked, the table is 52 rem wide and the page says "Swipe sideways to see all 18 columns. Tap an element for its details." Tick the box again for the whole table. In fit mode the atomic number is not on the cell, so open the panel to read it.

Some cells are grey and the legend says "No data".

This is not an error. The heat map only colours elements that have a value for the chosen property. Electronegativity is missing for helium, neon, argon, lawrencium and the superheavy elements, and atomic radius is missing for 27 elements. Hovering over a grey cell shows a dash. "Atomic mass" is the one property that has a value for all 118 elements.

It says "Could not create the picture of the table. Please try again."

"Download PNG" and "Print / save as PDF" draw the table on a 2339 × 1654 pixel canvas. The message appears under the buttons when the browser cannot make that canvas or cannot turn it into a PNG. The buttons are disabled while the picture is being made. Try again, try another browser, or use "Download CSV" to get the data instead.

How it compares

Use this as a quick reference and study aid: 118 elements with 16 fields each, a heat map, a quiz, and exports you can copy, print or open in a spreadsheet. It is not an authoritative data source. The page itself says the values are for reference only, many superheavy elements have no data, and it shows one year of discovery per element but no isotopes, spectra, compounds or safety information. For work where a figure matters, such as an exam answer or a report, check it against your textbook or a source you are required to cite. Compared with a printed wall chart, you can search, copy a value and colour the table by a property, and nothing is uploaded when you do.