We are planning a May trip to Grand Canyon, Zion and Bryce Canyon National Parks, and hope to reserve single nights at each of the park lodges near the visitor centers. One of us has some asthma problems, and can be affected by extremely high altitudes. Can anyone provide approximate altitudes near the visitor centers and lodges in the parks where we'll be staying overnights?

You can use Google Maps' terrain view to get the elevation of any location.

Roughly
Zion Lodge 4200'
Grand Canyon South Rim is 7000'
Bryce 7900'

Also, the GC north rim is about 8,200 ft

Clarification: We plan on the south rim at GC Village, not north rim. Thanks for referring me to Google maps "terrain". It appears Bryce Canyon to be at 8,200', Zion at 4,200' and GC Village at 6,800'. TripPointer