Canon RF 100-500mm f/4.5-7.1 L IS USM vs Canon RF 100-400mm f/5.6-8 IS USM

Both are Canon RF mount zooms for telephoto and sports & action — here's how the specs differ and which to pick. Every spec is from the manufacturer's own catalog.

Last verified 2026-06-21 · Canon RF mount · prices change — check the retailer

Spec	Canon RF 100-500mm f/4.5-7.1 L IS USM	Canon RF 100-400mm f/5.6-8 IS USM
Focal length	100-500mm	100-400mm
Max aperture	f/4.5-7.1	f/5.6-8
Type	zoom	zoom
Coverage	full-frame	full-frame
Mount	Canon RF	Canon RF

Which should you buy?

• the Canon RF 100-500mm f/4.5-7.1 L IS USM opens wider (f/4.5-7.1) — brighter in low light and more background blur
• the Canon RF 100-500mm f/4.5-7.1 L IS USM covers 100-500mm and the Canon RF 100-400mm f/5.6-8 IS USM covers 100-400mm — pick the range that matches what you shoot

Where to buy

Check the Canon RF 100-500mm f/4.5-7.1 L IS USM price on Amazon →

Check the Canon RF 100-400mm f/5.6-8 IS USM price on Amazon →

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FAQ

What's the difference between the Canon RF 100-500mm f/4.5-7.1 L IS USM and the Canon RF 100-400mm f/5.6-8 IS USM?
The Canon RF 100-500mm f/4.5-7.1 L IS USM is 100-500mm f/4.5-7.1 zoom, full-frame; the Canon RF 100-400mm f/5.6-8 IS USM is 100-400mm f/5.6-8 zoom, full-frame. Both fit the Canon RF mount.

Which is better in low light, the Canon RF 100-500mm f/4.5-7.1 L IS USM or the Canon RF 100-400mm f/5.6-8 IS USM?
The Canon RF 100-500mm f/4.5-7.1 L IS USM — its f/4.5-7.1 maximum aperture lets in more light and gives more background blur than the f/5.6-8 of the other.

Do the Canon RF 100-500mm f/4.5-7.1 L IS USM and Canon RF 100-400mm f/5.6-8 IS USM fit the same camera?
Yes — both are Canon RF mount lenses, so they fit Canon EOS R series (full-frame R5/R6/R8) and APS-C (R7/R10/R50).

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