Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Canon - EOS R5 C | Sony - FX3 |
|---|---|---|
| Max video | 8K | 4K120 |
Between the EOS R5 C and FX3, the EOS R5 C comes out ahead in max video, while the FX3 wins on several specs. Overall, the EOS R5 C scores 71 and the FX3 scores 63.1 on our Mars Score.
Which should you buy?
The EOS R5 C edges ahead on the Mars Score (71 vs 63.1), but the 7.9-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the EOS R5 C if you care most about max video. The biggest gaps in its favor are max video. The single most decisive one: Max video: 8K (vs 4K120).
The FX3 similarly does not carry a headline advantage on the popular specs — look at the full table for category-specific deltas.
Both ship with comparable optical zoom, sensor size, xlr input, so those specs do not separate the two — focus on the differences below.
Bottom line: the EOS R5 C is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Canon - EOS R5 C or Sony - FX3?
Canon - EOS R5 C leads the current Mars Score by 7.9 points.The more useful decision is the trade-off behind that result: compare max video against the way you will actually use the product.
Choose Canon - EOS R5 C if…
Canon - EOS R5 C has the measurable edge on max video.
Choose Sony - FX3 if…
Sony - FX3 does not lead a decisive measured field here, so choose it for price, ecosystem, design, or availability when those matter more to you.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Canon - EOS R5 C wins
- ▲Max video: 8K (vs 4K120).
Why Sony - FX3 wins
- No decisive advantages.
Spec comparison
Video
| Spec | Canon - EOS R5 C | Sony - FX3 |
|---|---|---|
| Max video | 8Klead | 4K120 |
| Optical zoom | 0 | 0 |
| Sensor sizeⓘ | Full Frame | Full Frame |
Audio
| Spec | Canon - EOS R5 C | Sony - FX3 |
|---|---|---|
| XLR input | true | true |
| Headphone jack | true | true |
Design
| Spec | Canon - EOS R5 C | Sony - FX3 |
|---|---|---|
| Weight | 770 g | 715 glead |
| Articulating screen | true | true |