| Part of speech | common noun |
|---|---|
| Hyphenation | ja·nu·ar·o |
| Singular | Plural | |
|---|---|---|
| Nominative | januaro | januaroj |
| Accusative | januaron | januarojn |
| Afrikaans | Januarie |
|---|---|
| Albanian | janar |
| Catalan | gener |
| Czech | leden |
| Danish | januar; glugmåned |
| Dutch | januari; louwmaand |
| English | January |
| Faeroese | januar |
| Finnish | tammikuu |
| French | janvier |
| German | Januar; Hartung; Hartmond; Hartmonat; Eismond; Eismonat; Schneemond; Schneemonat; Jänner |
| Greek | Γενάρης; Ιανουάριος |
| Hungarian | január |
| Icelandic | janúar |
| Italian | gennaio |
| Jamaican Patois | Janiweri |
| Latin | Ianuarius |
| Low German | januaar; januaarmånd; sneymånd; januari |
| Luxemburgish | Januar |
| Malay | bulan Januari; Januari |
| Norwegian | januar |
| Papiamento | yanüari; yanuari |
| Polish | styczeń |
| Portuguese | Janeiro |
| Romanian | ianuarie |
| Saterland Frisian | Januar |
| Scots | Januar |
| Scottish Gaelic | am Faoilteach |
| Spanish | enero |
| Swahili | Januari |
| Swedish | januari |
| Thai | มกราคม |
| Turkish | ocak ayı |
| Welsh | Ionawr |
| West Frisian | jannewaris |