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Read the articleRoman numerals 1 to 100: the chart and the 4 rules
A Roman numerals chart from 1 to 100, the 7 symbols, the 4 rules for writing them and the mistakes pupils make most often (IIII, IL, VV), with a game to practise.
Pupils meet Roman numerals everywhere: on clock faces, in chapter headings, in the names of kings and queens and in film credits. Yet many read XL as 60 or write IIII for 4. With 7 symbols and 4 rules, the whole system fits on one page.
The 7 symbols
I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1000. The values always grow the same way: multiply by 5, then by 2, and so on (1, 5, 10, 50, 100, 500, 1000). There is no symbol for zero: the Romans did not need one to write their numbers.
The 4 rules
- Write from largest to smallest, and add: XVI = 10 + 5 + 1 = 16.
- A smaller symbol before a larger one is subtracted: IV = 5 − 1 = 4. There are only six cases: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).
- Never more than three of the same symbol: 4 is IV, not IIII. V, L and D never repeat.
- Write place by place: thousands, then hundreds, tens and ones. 1947 = M + CM + XL + VII, so MCMXLVII.
The fourth rule is the most useful in class: it links Roman numerals to the place value pupils already know.
The chart from 1 to 100
Each row starts with a ten; each column adds ones. To write 47, take the row for 40 (XL) and the column for 7 (VII): XLVII. 100 is C.
| tens + ones | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|
| 0 | – | I | II | III | IV | V | VI | VII | VIII | IX |
| 10 | X | XI | XII | XIII | XIV | XV | XVI | XVII | XVIII | XIX |
| 20 | XX | XXI | XXII | XXIII | XXIV | XXV | XXVI | XXVII | XXVIII | XXIX |
| 30 | XXX | XXXI | XXXII | XXXIII | XXXIV | XXXV | XXXVI | XXXVII | XXXVIII | XXXIX |
| 40 | XL | XLI | XLII | XLIII | XLIV | XLV | XLVI | XLVII | XLVIII | XLIX |
| 50 | L | LI | LII | LIII | LIV | LV | LVI | LVII | LVIII | LIX |
| 60 | LX | LXI | LXII | LXIII | LXIV | LXV | LXVI | LXVII | LXVIII | LXIX |
| 70 | LXX | LXXI | LXXII | LXXIII | LXXIV | LXXV | LXXVI | LXXVII | LXXVIII | LXXIX |
| 80 | LXXX | LXXXI | LXXXII | LXXXIII | LXXXIV | LXXXV | LXXXVI | LXXXVII | LXXXVIII | LXXXIX |
| 90 | XC | XCI | XCII | XCIII | XCIV | XCV | XCVI | XCVII | XCVIII | XCIX |
Roman Numeral TempleRead, write and compare Roman numerals: every correct answer adds a stone to the temple.See the game
The most common mistakes
- Adding everything: the pupil reads XL as 10 + 50 = 60. Have them spot the six subtracting pairs first.
- Repeating four times: IIII for 4, XXXX for 40. Many clocks show IIII: it is a clockmakers’ tradition, not the rule.
- Subtracting any symbol: IL for 49 instead of XLIX, IC for 99 instead of XCIX. Only I, X and C go in front, and only before the next two symbols.
- Repeating V, L or D: VV for 10. It should be X.
- Thinking the longest numeral is the greatest: VIII (8) is longer than IX (9) but smaller. Comparing starts with working out the values.
A four-step sequence
- I, V and X up to 20, using a clock face.
- L and C up to 100, writing the ten first, then the ones.
- D and M, then years: 2026 is MMXXVI.
- Reading in context: chapters, clocks, film credits.
Writing a number in Roman numerals starts with splitting it into hundreds, tens and ones, which makes it a good time to revisit place value.
The Number FactoryBuild, write, break apart and place numbers with flats, rods and cubes.See the game