Did runes have numbers?

The short answer is that they did not. None of the runic alphabets has a set of numerals the way Latin has I, V and X or Greek has its alphabetic numbers. A carver who needed to write a number wrote the word for it.

The flat statement is deliberate, because it rules out a whole family of claims. A rune has a sound and a name; it does not have a numeric value. Systems that assign each rune a number (usually its position in the futhark) and read meaning off the total are doing arithmetic the historical script never supported.

The one exception, and it is late

From the Middle Ages, Scandinavians made perpetual calendars on flat sticks and boards: the runic almanac, known in Norway as the primstav and in Iceland as rímstafir. These are the one place runes were used as numbers, and the way they did it is specific.

A calendar stick needs two repeating cycles. The days of the week were marked with the first seven runes of the futhark, running over and over down the stick. The years were marked with the golden number, the position of a year within the nineteen-year lunar cycle, which is what the date of Easter is calculated from.

Why the alphabet had to be extended

Here is the problem. The golden number runs from 1 to 19. The Younger Futhark has sixteen runes. Sixteen is not nineteen, so three more signs had to be invented, and they were, purely to fill the gap.

They are not runes in the ordinary sense at all. They write no sound, they head no rune-poem stanza, and outside a calendar they mean nothing. They are closer to a numeral than to a letter, which makes them the exception that shows how firmly the rest of the alphabet was not numeric.

What this does not mean

• Runes do not have numeric values. Numbering them 1–24 by their position in the futhark is a modern convenience for talking about them, not a property they carry.
• There is no runic numerology. Systems that add up rune positions to produce a reading are 20th-century constructions. See rune meanings.
• Counting marks are not runes. Inscriptions sometimes tally things with plain strokes. A stroke is a stroke, and reading a row of them as repeated isaz is a common error on damaged objects.
• The calendar is medieval and Christian. The runic almanac belongs with medieval runes, several centuries after the Viking Age, and its whole purpose is calculating a Christian festival.