To check the battery level of soundcore Sleep A10 earbuds, you can follow these steps:

1. After the earbuds are paired with the soundcore app, you can check it via the app.

2. When the earbuds are in the charging case, the three lights in the charging case blink:

- When three LED lights are white, the case is on more than 70% battery.

- When the left two LED lights are white and the right LED is off, the case is on 30%-70%.

- When the left LED is white and the right two LED's are off, the case is on 5%-30%.

- When the left LED blinks and the right two LED's are off, the case is on less than 5%.