GlyphIndexSecond derivative
If f(x) = x³, then f″(x) = 6x.
The double prime denotes a second derivative here.
Double-prime sign
The double-prime sign ″ is one character. It can mark a second derivative or a measurement such as angular seconds, depending on context.
DOUBLE PRIME
Appearance can vary by font.
Character details
♡→✦
3 code pointsMeaning and context
The double-prime sign ″ is one character. It can mark a second derivative or a measurement such as angular seconds, depending on context.
How to use it
Keep it distinct from two apostrophes and a closing quotation mark. Spell out the unit when the intended interpretation might be ambiguous.
Examples
Angular seconds
1′ = 60″
This line compares angular minutes and seconds.
Similar shapes, different characters
Right double quotation mark
U+201DA closing quote is punctuation rather than a prime.
DetailsTwo prime characters
U+2032 U+2032This sequence has two code points; ″ has one.
DetailsSources and method
- Unicode 18.0.0 character database — Pinned standard character identities and properties; the application computes UTF encodings from the original text.
- Unicode character code charts — Reference glyphs are not a guarantee of the appearance in a user’s font.