I've owned the Mi Band 1S for about a month now and I'm really pleased. For $15 it does everything I would want a fitness tracking bracelet for. 

One feature that I use often is the step counter feature. Steps are counted automatically by the Mi Band 1S and synced automatically to the Mi Fit app by Bluetooth.

Before even ordering a Mi Band I've read people saying that the Mi Band doesn't count steps accurately. I can't take comments like that at face value so I had to test it myself.

The Mi Band 1000 step test

I took my Mi Band to my favorite walking path. A nice level and straight path that would be the testing ground for a 1000 step test of the Mi Band's step counting accuracy.

I recorded the number of steps shown in the MI Fit app before I began. 

6626 steps.

Then I walked 1000 steps along the walking path, carefully counting each step, until I reached 1000 steps. Then I stopped and looked at the steps shown in the Mi Fit app again. 

7626 steps.

It was accurate. The Mi Band 1S had no problem accurately counting my steps. 

My phone, on the other hand, a Galaxy Note 4 with the S-Health app, over counted my steps as 1009 steps instead of 1000.

So, yes, the Mi Band 1S was accurate in counting my steps. No error in 1000 steps seemed pretty good. 

I think it's worth pointing out though, that my test occurred in some favorable conditions. I walked at a steady gate, on a smooth surface, and I kept my movement constant without any stopping. These should be conditions that would make it easy for a pedometer to count steps.

At least in optimal conditions, the Mi Band 1S works just fine and I'm happy with it.