iPad Pro slower Wi-Fi speeds than iPhone and iMac

Have you updated your iPad to the most recent version of iOS/iPadOS? Are both your iPad and iPhone running the same version of iOS/iPadOS?

These support pages may be helpful with initial troubleshooting of WiFi connection difficulties:

If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network - Apple Support

Recommended settings for Wi-Fi routers and access points - Apple Support

Does your WiFi router support both 5GHz and 2.4GHz networks? If so, try splitting the two bands to use different Network Names / SSID - and then ensure that all devices are connecting to either the 5GHz or 2.4GHz channel. If you are using the same Network Name / SSID for both bands, your devices may be connecting to different WiFi bands - and produce different throughput measurements.

Having established that your are using the same WiFi band to connect and measure performance for different devices, if unexplained differences remain, a restart of your WiFi Router may help. To restart you home router, disconnect power - then wait at least 30 seconds before restarting. When you router has rebooted (which may take several minutes), force-restart your iPad and iPhone:

• Force restart iPad - Apple Support
• Force restart iPhone - Apple Support

You might be best advised to seek assistance directly from from Apple Support - and request a remote diagnostic test. You can contact the Support Team using the Support link at top-right or bottom-left of this page.

Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/gb/app/apple-support/id1130498044

A forced-restart of the iPad was one of the recommended steps included within my initial reply…