748 distinct masculine names and 255 distinct feminine names were recorded in the 1427 Catasto of Florence. The following 123 pairs of names from the 1427 Catasto of Florence show that there was widespread feminization of masculine names, both common and uncommon ones; 29% of the masculine names have a corresponding feminine form, and 48% of the feminine names are feminized forms of masculine names. The feminized forms show a fairly distinct pattern: In general, masculine terminal -o and -i changed to -a, and terminal -e and -a remained unchanged. There are few exceptions to this pattern.
In constructing this list, I considered only direct matches (e.g., ones where the only difference between the masculine and the feminine forms was the final vowel), with the exception of the pairs Agabito/Agabitta and Camillo/Cammilla. This means that feminine names that are feminization of diminutives that do not show up in the Catasto are not listed, nor are spelling variants, unless the variant occurs in both the men's and the women's names.
| Masculine | Number | Feminine | Number |
| Agabito | 1 | Agabitta | 1 |
| Agnesa | 1 | Agnesa | 1 |
| Agnolo | 86 | Agnola | 26 |
| Alamanno | 5 | Alamanna | 1 |
| Aldighieri | 1 | Aldighiera | 1 |
| Alessandro | 11 | Alessandra | 3 |
| Andrea | 206 | Andrea | 206 |
| Andreolo | 1 | Andreola | 1 |
| Antonio | 661 | Antonia | 84 |
| Apollonio | 5 | Apollonia | 15 |
| Banco | 5 | Banca | 2 |
| Bartolo | 72 | Bartola | 5 |
| Bartolomeo | 290 | Bartolomea | 46 |
| Bello | 1 | Bella | 5 |
| Bene | 2 | Bene | 1 |
| Benedetto | 70 | Benedetta | 6 |
| Benevenuto | 1 | Benvenuta | 2 |
| Bernardo | 132 | Bernarda | 5 |
| Bertino | 4 | Bertina | 1 |
| Betto | 18 | Betta | 17 |
| Bettino | 10 | Bettina | 1 |
| Biagio | 43 | Biagia | 5 |
| Biondo | 2 | Bionda | 2 |
| Buono | 14 | Buona | 6 |
| Camillo | 1 | Camilla | 1 |
| Camillo | 1 | Cammilla | 1 |
| Cecco | 38 | Cecca | 43 |
| Chiaro | 5 | Chiara | 3 |
| Ciano | 1 | Ciana | 1 |
| Ciulo | 1 | Ciula | 1 |
| Corradino | 1 | Corradina | 1 |
| Cristofano | 91 | Cristofana | 6 |
| Deo | 3 | Dea | 2 |
| Domenico | 234 | Domenica | 13 |
| Dono | 2 | Dona | 1 |
| Donato | 37 | Donata | 1 |
| Donnino | 6 | Donnina | 1 |
| Dore | 1 | Dora | 1 |
| Duccio | 11 | Duccia | 1 |
| Feo | 5 | Fea | 4 |
| Felice | 6 | Felice | 6 |
| Filippo | 134 | Filippa | 21 |
| Fino | 1 | Fina | 1 |
| Fiore | 1 | Fiore | 10 |
| Franco | 5 | Franca | 1 |
| Francesco | 390 | Francesca | 34 |
| Franchino | 1 | Franchina | 1 |
| Frosino | 30 | Frosina | 1 |
| Gentile | 7 | Gentile | 1 |
| Geri | 14 | Gera | 2 |
| Gherardo | 26 | Gherarda | 2 |
| Giano | 5 | Giana | 1 |
| Giannotto | 2 | Gianotta | 1 |
| Gilio | 2 | Gilia | 1 |
| Giovanni | 739 | Giovanna | 39 |
| Girolama | 12 | Girolama | 1 |
| Gostanzo | 1 | Gostanza | 19 |
| Grazia | 3 | Grazia | 1 |
| Guglielmino | 2 | Gugliemina | 1 |
| Guido | 47 | Guida | 4 |
| Iacopo | 329 | Iacopa | 15 |
| Lapo | 17 | Lapa | 8 |
| Lapaccio | 3 | Lapaccia | 3 |
| Leonardo | 82 | Leonarda | 12 |
| Lippo | 8 | Lippa | 1 |
| Lisa | 1 | Lisa | 45 |
| Lore | 1 | Lora | 2 |
| Lorenzo | 216 | Lorenza | 12 |
| Lotto | 13 | Lotta | 1 |
| Lottieri | 2 | Lottiera | 2 |
| Luca | 82 | Luca | 4 |
| Lucio | 1 | Lucia | 14 |
| Manetto | 9 | Manetta | 1 |
| Mariano | 20 | Marianna | 1 |
| Maruccio | 1 | Maruccia | 1 |
| Maso | 44 | Masa | 4 |
| Matteo | 136 | Mattea | 28 |
| Mea | 2 | Mea | 30 |
| Michelino | 2 | Michelina | 1 |
| Migliore | 5 | Migliore | 3 |
| Mino | 3 | Mina | 1 |
| Naldino | 1 | Naldina | 1 |
| Nanni | 92 | Nanna | 51 |
| Nardo | 25 | Narda | 1 |
| Nastagio | 2 | Nastagia | 3 |
| Nencio | 10 | Nencia | 4 |
| Neri | 37 | Nera | 5 |
| Neso | 1 | Nese | 2 |
| Niccolo | 259 | Niccola | 1 |
| Nigi | 4 | Nigia | 1 |
| Nofri | 24 | Nofra | 6 |
| Nuto | 5 | Nuta | 1 |
| Nutino | 1 | Nutina | 1 |
| Onesto | 1 | Onesta | 1 |
| Orso | 2 | Orsa | 1 |
| Orsino | 2 | Orsina | 1 |
| Pace | 9 | Pace | 2 |
| Pagolo | 132 | Pagola | 10 |
| Papero | 1 | Papera | 14 |
| Papino | 2 | Papina | 1 |
| Piccardo | 1 | Piccarda | 1 |
| Piero | 391 | Piera | 53 |
| Pippo | 23 | Pippa | 19 |
| Ricco | 6 | Ricca | 1 |
| Riccardo | 9 | Riccarda | 1 |
| Rosso | 6 | Rossa | 1 |
| Salvestro | 47 | Salvestra | 4 |
| Sandro | 40 | Sandra | 19 |
| Santi | 23 | Santa | 5 |
| Simone | 132 | Simona | 18 |
| Stefano | 69 | Stefana | 2 |
| Taddeo | 33 | Taddea | 14 |
| Tedesco | 1 | Tedesca | 1 |
| Tommaso | 138 | Tommasa | 19 |
| Tone | 2 | Tona | 1 |
| Toro | 1 | Tora | 1 |
| Ulivo | 2 | Uliva | 2 |
| Vaggio | 1 | Vaggia | 6 |
| Vangelista | 2 | Vangelista | 2 |
| Vanni | 20 | Vanna | 5 |
| Verdiano | 1 | Verdiana | 1 |
| Vettorio | 6 | Vettoria | 1 |
| Zanobi | 88 | Zanobia | 20 |
References
Arval Benicoeur, "Feminine Given Names from the Online Catasto of Florence of 1427" (WWW: Academy of Saint Gabriel, 1998).
Ferrante laVolpe, "Men's names from Florence, 1427" (WWW: Self-published, 1996; Academy of Saint Gabriel, 1999).