Superscript Seven

Commonly a power of seven or footnote number seven. Right after a number or letter it is an exponent: x⁷ is x multiplied by itself seven times, and 10⁷ is 10,000,000. Right after a word or sentence it points to note 7 at the bottom of the page or the end of the text.

In science you may also see it before an element symbol: ⁷Li is lithium-7, the lithium atom with a mass number of 7. Position does all the work; the character itself only says "raised 7".

Why does ⁷ sometimes look out of line with ¹²³?

They were encoded separately, so fonts may draw them differently. ¹, ² and ³ already existed in the old Western European character set (Latin-1), which is one reason more keyboard layouts offer them. ⁴ to ⁹, ⁷ among them, were added in a separate Unicode block, and depending on the font (or a fallback font stepping in) they can come out at a different size or height. A number like 10¹⁷ can therefore look uneven.

In a word processor or web page, ordinary superscript formatting gives a consistent result. Use ⁷ where formatting is lost: messages, social posts and spreadsheet cells. In usernames and file names it works too, though some systems quietly turn it back into a plain 7.