| Name | Lines of code | Maintainability | Test coverage |
| src/PluralResolver.js | 163 | D 1 day | |
| typescript/options.d.ts | 180 | A 0 mins | |
| src/utils.js | 196 | C 1 day | |
| typescript/t.v4.d.ts | 199 | A 0 mins | |
| typescript/t.d.ts | 207 | A 0 mins | |
| src/BackendConnector.js | 216 | B 6 hrs | |
| src/Interpolator.js | 235 | C 1 day | |
| src/i18next.js | 522 | F 4 days | |
| src/Translator.js | 532 | F 1 wk |