Is it normal for wireless data speed to be Sporadic

[max2]

Like for example 1 MB/sec for one sec then 3 MB/sec then 900KB/sec and so on.

 

[Apple_Robert]

It is not unusual. There are a lot of variables involved between your device, the service provider and their servers, and the internet.

 

[MacNut]

The amount of people on the network at any given time. Your location and any obstructions in the way all affect speeds.

 

[vrBrew]

What are you doing and how are you measuring? TCP can constantly change due to delay/jitter/reordering when mixed with windowing. Not only that but wireless can change as well, changes in tx/rx signal strength will change max throughput.