1~10: I II III IV V VI VII VIII IX X
11~20: XI XII XIII XIV XV XVI XVII XVIII XIX XX
21~30: XXI XXII XXIII XXIV XXV XXVI XXVII XXVIII XXIX XXX
31~40: XXXI XXXII XXXIII XXXIV XXXV XXXVI XXXVII XXXVIII XXXIX XL
41~50: XLI XLII XLIII XLIV XLV XLVI XLVII XLVII XLIX L
其中，I 为1
V为5
X为10
L为50

I - 1 unus
II - 2 duo
III - 3 tres
IV - 4 quattuor
V - 5 quinque
VI - 6 sex
VII - 7 septem
VIII - 8 octo
IX - 9 novem
X - 10 decem
XI - 11 undecim
XII - 12 duodecim
XIII - 13 tresdecim
XIV - 14 quattuordecim
XV - 15 quindecim
XVI - 16 sedecim
XVII - 17 septendecim
XVIII - 18 duodeviginti
XIX - 19 undeviginti
XX - 20 viginti
XXI - 21 viginti unus
XXII - 22 viginti duo
XXVIII - 28 duodetriginta
XXIX - 29 undetriginta
XXX - 30 triginta
XL - 40 quadraginta
L - 50 quinquaginta


LI, 51
LV, 55
LX, 60
LXV, 65
LXX, 70
LXXX, 80
XC, 90
XCIII, 93
XCV, 95
XCVIII, 98
IC, 99
C, 100
CC, 200
CCC, 300
CD, 400
D, 500
DC, 600
DCC, 700
DCCC, 800
CM, 900
M, 1000
MC, 1100
MCD, 1400
MD, 1500
MDC, 1600
MDCLXVI, 1666
MDCCCLXXXVIII, 1888
MDCCCXCIX, 1899
MCM, 1900
MCMLXXVI, 1976
MCMLXXXIV, 1984
MCMXC, 1990
MM, 2000