Hi there! There is a tool called tread depth gauge to check your tyre. It is the most accurate way to determine if you need to change your tyres besides going all the way to the workshop to check. Ensure that the remaining tread depth of every tyre is at least 1.6mm. If the depth is lesser than 1.6mm, it's time to change your tyre!
To find out more tyre safety tips, you can read the full article here: https://bit.ly/2P0InTf