| Native Speakers | Language | % Correct |
|---|---|---|
| 150 million | Russian | 99%
|
| 32 million | Ukrainian | 97%
|
| 38 million | Polish | 96%
|
| 24 million | Serbo-Croatian | 96%
|
| 5.2 million | Slovak | 95%
|
| 7.8 million | Bulgarian | 93%
|
| 10 million | Czech | 93%
|
| 9 million | Serbian | 90%
|
| 2.1 million | Slovene | 90%
|
| 1.4 million | Macedonian | 87%
|
| 3.3 million | Belarusian | 86%
|
| 2.5 million | Bosnian | 86%
|
| 5.6 million | Croatian | 83%
|
| 240k | Montenegrin | 74%
|
| 623k | Rusyn | 59%
|
| 20k | Sorbian | 55%
|
| 50k | Kashubian | 49%
|
| 522k | Silesian | 48%
|