Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Sony - α6700 | Sony - α9 III |
|---|---|---|
| Weight | 493 g | 703 g |
| Megapixels | 26 MP | 24 MP |
| Sensor size | APS-C | Full Frame |
Between the α6700 and α9 III, the α6700 comes out ahead in weight / megapixels, while the α9 III wins on sensor size. Overall, the α6700 scores 71.4 and the α9 III scores 71.7 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (71.4 vs 71.7). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
Pick the α6700 if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are weight, megapixels. The single most decisive one: Weight — 210.00 g less. 493 vs 703.
Pick the α9 III if you care most about sensor size. Its strongest claims are sensor size. The single most decisive one: Sensor size: Full Frame (vs APS-C).
Both ship with comparable max video, in-body stabilization, af points, so those specs do not separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.
Which should you buy: Sony - α6700 or Sony - α9 III?
Sony - α9 III leads the current Mars Score by 0.3 points.The more useful decision is the trade-off behind that result: compare megapixels, sensor size, weight against the way you will actually use the product.
Choose Sony - α6700 if…
Sony - α6700 has the measurable edge on weight g, megapixels.
Choose Sony - α9 III if…
Sony - α9 III has the measurable edge on sensor size.
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 Sony - α6700 wins
- ▲Weight — 210.00 g less. 493 vs 703.
- ▲Megapixels — 8.33% more. 26 MP vs 24 MP.
Why Sony - α9 III wins
- ▲Sensor size: Full Frame (vs APS-C).
Spec comparison
Sensor
| Spec | Sony - α6700 | Sony - α9 III |
|---|---|---|
| Sensor sizeⓘ | APS-C | Full Framelead |
| Megapixels | 26 MPlead | 24 MP |
| Max ISO | 32000 | 51200lead |
Video
| Spec | Sony - α6700 | Sony - α9 III |
|---|---|---|
| Max video | 4K120 | 4K120 |
| RAW video | false | truelead |
| Log profileⓘ | true | true |
Autofocus
| Spec | Sony - α6700 | Sony - α9 III |
|---|---|---|
| AF pointsⓘ | 759 | 759 |
| Eye AFⓘ | true | true |
| In-body stabilizationⓘ | true | true |
Body & Controls
| Spec | Sony - α6700 | Sony - α9 III |
|---|---|---|
| Weight | 493 glead | 703 g |
| Weather sealedⓘ | true | true |
| Dual card slotsⓘ | false | truelead |