40 in Roman Numerals = XL
Forty is XL, ten before fifty, not four X strokes. It trips people up because the subtractive rule jumps a whole tens place here.
What is 40 in Roman numerals?
How XL is formed
Reading left to right, 40 breaks into these additive parts. Each Roman symbol is added in turn to reach the total.
XL = 40 = 40.
The shape of XL
- Written out, XL runs 2 characters, against 5 for 39 (XXXIX) and 3 for 41 (XLI).
- One pair inside XL is subtractive: XL makes 40 by putting the smaller glyph first. The rest of the numeral is plain addition.
- XL anchors its ten: the numerals from 40 to 49 all open with XL before their unit glyphs.
- XL uses 2 different symbols and repeats none of them: one appearance each.
- Among 40 to 49, 40 is the most compact: no other numeral in its ten gets down to 2 characters.
Where 40 in Roman numerals is used
- Chapter, act or appendix numbering in books and plays.
- Super Bowl XL and other numbered championship events.
- Outlines, exam questions and list items in formal documents.
Good to know about 40
- Forty, XL, doubles as a clothing size, which keeps the numeral in everyday view.
Convert another number
40 is written XL in Roman numerals.
Frequently asked questions
How do you write 40 in Roman numerals?
Write 40 as XL, combining XL. Start from the largest value that fits and work down until nothing is left over.
Why is 40 not written XXXX?
XL uses the subtractive rule: a smaller symbol placed before a larger one is taken away, so you never repeat a symbol four times. XXXX breaks that rule, which is why XL is the only correct form.
Which Super Bowl is XL?
Super Bowl XL is the 40th Super Bowl, played in 2006. The NFL sets its championship number in Roman numerals, which is why so many people look up values like XL.
How is XL broken down?
XL breaks down as XL (40), so XL = 40 = 40.