Depends

Can I use an XD cassette on an XDR body (and vice versa)?

One way only. An XD cassette (MTB) can fit on an XDR body by adding a 1.85 mm spacer. The other way around, an XDR cassette (road) will NOT fit on an XD body because it is 1.85 mm wider.

Standards involved

SRAM XD Driver A dedicated body for SRAM cassettes that start at 10 teeth (MTB), e.g. 10-50 / 10-52. SRAM XDR An XD variant that is 1.85 mm wider, for road/gravel (10t cassettes, e.g. SRAM 12-speed AXS Flattop).

What you need — before you buy

It depends on the exact parts: read the answer above and check the manufacturer's spec for your specific model and year.
When in doubt, keep the same brand and generation across the components that must work together.
Match the part to your exact hub/frame: check brand, model and year. Don't choose a freehub body or component by standard name alone.

Can I use an XD cassette on an XDR body (and vice versa)?

Standards involved

What you need — before you buy

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