<table border><tr><td></td><th align='center' colspan='8'>Year to letter</th></tr><tr align='right'><td></td>
<td> 0<br> 8<br>16<br>24<br>32<br>40<br>48<br>56<br>64<br>72<br>80<br>88<br>96</td>
<td> 1<br> 9<br>17<br>25<br>33<br>41<br>49<br>57<br>65<br>73<br>81<br>89<br>97</td>
<td> 2<br>10<br>18<br>26<br>34<br>42<br>50<br>58<br>66<br>74<br>82<br>90<br>98</td>
<td> 3<br>11<br>19<br>27<br>35<br>43<br>51<br>59<br>67<br>75<br>83<br>91<br>99</td>
<td> 4<br>12<br>20<br>28<br>36<br>44<br>52<br>60<br>68<br>76<br>84<br>92<br>&nbsp;</td>
<td> 5<br>13<br>21<br>29<br>37<br>45<br>53<br>61<br>69<br>77<br>85<br>93<br>&nbsp;</td>
<td> 6<br>14<br>22<br>30<br>38<br>46<br>54<br>62<br>70<br>78<br>86<br>94<br>&nbsp;</td>
<td> 7<br>15<br>23<br>31<br>39<br>47<br>55<br>63<br>71<br>79<br>87<br>95<br>&nbsp;</td>
</tr>
<tr align='center'><td>1 - 8</td><td>ch</td><td>bg</td><td>bg</td><td>bg</td><td>cg</td><td>bg</td><td>bg</td><td>bg</td></tr>
<tr align='center'><td>9 - 19</td><td>dh</td><td>ch</td><td>ch</td><td>ch</td><td>dh</td><td>ch</td><td>ch</td><td>ch</td></tr>
<tr align='center'><td>20 - 100</td><td>cg</td><td>ch</td><td>ch</td><td>ch</td><td>cg</td><td>ch</td><td>ch</td><td>ch</td></tr>
<tr align='center'><td>101 - 108</td><td>bg</td><td>bg</td><td>bg</td><td>bg</td><td>bf</td><td>bg</td><td>bg</td><td>bg</td></tr>
<tr align='center'><td>109 - 200</td><td>cg</td><td>ch</td><td>ch</td><td>ch</td><td>cg</td><td>ch</td><td>ch</td><td>ch</td></tr>
<tr align='center'><td>201 - 300</td><td>bf</td><td>bg</td><td>bg</td><td>bg</td><td>bf</td><td>bg</td><td>bg</td><td>bg</td></tr>
<tr align='center'><td>301 - 308</td><td>af</td><td>af</td><td>af</td><td>af</td><td>ae</td><td>af</td><td>af</td><td>af</td></tr>
<tr align='center'><td>309 - 400</td><td>bf</td><td>bg</td><td>bg</td><td>bg</td><td>bf</td><td>bg</td><td>bg</td><td>bg</td></tr>
</table>
<p><table border><tr><th align='center' colspan='5'>Beginning of Year</th></tr>
<tr align='center'><th>Year + 1791</th><th>a</th><th>b</th><th>c</th><th>d</th></tr>
<tr align='center'><td>Vendémiaire</td><td>+20 Sep<br>-10 Oct</td>
<td>+21 Sep<br>-9 Oct</td>
<td>+22 Sep<br>-8 Oct</td>
<td>+23 Sep<br>-7 Oct</td>
</tr>
<tr align='center'><td>Brumaire</td><td>+20 Oct<br>-11 Nov</td>
<td>+21 Oct<br>-10 Nov</td>
<td>+22 Oct<br>-9 Nov</td>
<td>+23 Oct<br>-8 Nov</td>
</tr>
<tr align='center'><td>Frimaire</td><td>+19 Nov<br>-11 Dec</td>
<td>+20 Nov<br>-10 Dec</td>
<td>+21 Nov<br>-9 Dec</td>
<td>+22 Nov<br>-8 Dec</td>
</tr>
<tr align='center'><td>Nivôse</td><td>+19 Dec</td>
<td>+20 Dec</td>
<td>+21 Dec</td>
<td>+22 Dec</td>
</tr>
<tr align='center'><th>Year + 1792</th><th>a</th><th>b</th><th>c</th><th>d</th></tr>
<tr align='center'><td>Nivôse</td><td>-12 Jan</td>
<td>-11 Jan</td>
<td>-10 Jan</td>
<td>-9 Jan</td>
</tr>
<tr align='center'><td>Pluviôse</td><td>+18 Jan<br>-13 Feb</td>
<td>+19 Jan<br>-12 Feb</td>
<td>+20 Jan<br>-11 Feb</td>
<td>+21 Jan<br>-10 Feb</td>
</tr>
<tr align='center'><td>Ventôse</td><td>+17 Feb</td>
<td>+18 Feb</td>
<td>+19 Feb</td>
<td>+20 Feb</td>
</tr>
</table>
<p><table border><tr><th align='center' colspan='5'>End of Year</th></tr>
<tr align='center'><th>Year + 1792</th><th>e</th><th>f</th><th>g</th><th>h</th></tr>
<tr align='center'><td>Ventôse</td><td>-12 Mar</td>
<td>-11 Mar</td>
<td>-10 Mar</td>
<td>-9 Mar</td>
</tr>
<tr align='center'><td>Germinal</td><td>+18 Mar<br>-13 Apr</td>
<td>+19 Mar<br>-12 Apr</td>
<td>+20 Mar<br>-11 Apr</td>
<td>+21 Mar<br>-10 Apr</td>
</tr>
<tr align='center'><td>Floréal</td><td>+17 Apr<br>-13 May</td>
<td>+18 Apr<br>-12 May</td>
<td>+19 Apr<br>-11 May</td>
<td>+20 Apr<br>-10 May</td>
</tr>
<tr align='center'><td>Prairial</td><td>+17 May<br>-14 Jun</td>
<td>+18 May<br>-13 Jun</td>
<td>+19 May<br>-12 Jun</td>
<td>+20 May<br>-11 Jun</td>
</tr>
<tr align='center'><td>Messidor</td><td>+16 Jun<br>-14 Jul</td>
<td>+17 Jun<br>-13 Jul</td>
<td>+18 Jun<br>-12 Jul</td>
<td>+19 Jun<br>-11 Jul</td>
</tr>
<tr align='center'><td>Thermidor</td><td>+16 Jul<br>-15 Aug</td>
<td>+17 Jul<br>-14 Aug</td>
<td>+18 Jul<br>-13 Aug</td>
<td>+19 Jul<br>-12 Aug</td>
</tr>
<tr align='center'><td>Fructidor</td><td>+15 Aug<br>-16 Sep</td>
<td>+16 Aug<br>-15 Sep</td>
<td>+17 Aug<br>-14 Sep</td>
<td>+18 Aug<br>-13 Sep</td>
</tr>
<tr align='center'><td>Sans-Culottides<br>Additional Days</td><td>+14 Sep</td>
<td>+15 Sep</td>
<td>+16 Sep</td>
<td>+17 Sep</td>
</tr>
</table>
<h3>How to convert 18 Brumaire VIII</h3>
<p>Look at the first table. The French Revolutionary year 
<strong>8</strong> 
belongs to the interval
<em>1&nbsp;-&nbsp;8</em> 
and its last two digits are 
<em>08</em>. 
The cell in the corresponding
line and column contains the two letters 
<em>ch</em>. 
<p>Look at the next two tables. The month 
<strong>Brumaire</strong> 
appears in the 
<em>Beginning of Year</em> 
table. Of the two letters 
<em>ch</em>, 
the letter 
<em>c</em> 
appears in the same table. The corresponding cell contains two formulas: 
<em>+22 Oct -9 Nov</em>. 
Choose the one that will convert the day number 
<strong>18</strong>
into a number in the proper range for the Gregorian month. That is, up to and including 
<strong>9 Brumaire</strong>, 
use the first formula 
<em>+22 Oct</em>, 
and later use the second formula 
<em>-9 Nov</em>.
Since the French Revolutionary day number is 
<strong>18</strong>, 
you use <em>-9 Nov</em>. Using the year formula next to the column headers, you get
<strong>9 November 1799</strong>.

<h3>Special cases</h3>
<p>For 
<strong>Additional Days</strong>,
there is only one formula, which is much simpler.
<p>For 
<strong>Nivôse</strong>,
the cell is split in two, because there are two formulas for the year,
<em>Year&nbsp;+&nbsp;1791</em>
and
<em>Year&nbsp;+&nbsp;1792</em>.
<p><strong>Ventôse</strong> 
is in both tables. For
<strong>Ventôse 8</strong>,
in column
<em>c</em>
you obtain the 
<em>+19 Feb</em>
formula, and in column
<em>h</em>
you obtain the 
<em>-9 Mar</em>
formula. Except for that, everything else is the same. That is, up to and including 
<strong>9 Ventôse</strong>, 
use the first formula 
<em>+19 Feb</em>, 
and later use the second formula 
<em>-9 Mar</em>.
For example, if you want to convert
<strong>18 Ventôse VIII</strong>, 
since the French Revolutionary day number is 
<strong>18</strong>, 
you use <em>-9 Mar</em>, and you get
<strong>9 March 1800</strong>.