Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | LG - C5 OLED 65 | LG - C5 OLED 77 |
|---|---|---|
| Screen size | 65 " | 77 " |
Between the C5 OLED 65 and C5 OLED 77, the C5 OLED 65 comes out ahead in several specs, while the C5 OLED 77 wins on screen size. Overall, the C5 OLED 65 scores 69 and the C5 OLED 77 scores 71.5 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (69 vs 71.5). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
The C5 OLED 65 does not pull ahead on any single popular-comparison spec — its strengths sit in the spec-table groups rather than the headline advantages.
Pick the C5 OLED 77 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are screen size. The single most decisive one: Screen size — 18.46% more. 77 " vs 65 ".
Both ship with comparable panel type, refresh rate, peak brightness, 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: LG - C5 OLED 65 or LG - C5 OLED 77?
LG - C5 OLED 77 leads the current Mars Score by 2.5 points.The more useful decision is the trade-off behind that result: compare screen size against the way you will actually use the product.
Choose LG - C5 OLED 65 if…
LG - C5 OLED 65 does not lead a decisive measured field here, so choose it for price, ecosystem, design, or availability when those matter more to you.
Choose LG - C5 OLED 77 if…
LG - C5 OLED 77 has the measurable edge on screen size in.
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 LG - C5 OLED 65 wins
- No decisive advantages.
Why LG - C5 OLED 77 wins
- ▲Screen size — 18.46% more. 77 " vs 65 ".
Spec comparison
Display
| Spec | LG - C5 OLED 65 | LG - C5 OLED 77 |
|---|---|---|
| Screen size | 65 " | 77 "lead |
| Panel typeⓘ | OLED | OLED |
| Resolutionⓘ | 4K | 4K |
| Refresh rateⓘ | 144 Hz | 144 Hz |
| Peak brightnessⓘ | 1300 nits | 1300 nits |
HDR & Smart
| Spec | LG - C5 OLED 65 | LG - C5 OLED 77 |
|---|---|---|
| Dolby Visionⓘ | true | true |
| HDR10+ⓘ | false | false |
| Smart OS | webOS | webOS |
| Dolby Atmosⓘ | true | true |
Gaming
| Spec | LG - C5 OLED 65 | LG - C5 OLED 77 |
|---|---|---|
| HDMI 2.1 portsⓘ | 4 | 4 |
| VRRⓘ | true | true |
| ALLM | true | true |
Frequently asked
Which is brighter, C5 OLED 65 or C5 OLED 77?+
C5 OLED 77 peaks at 1300 nits vs 1300 nits.
Which is better for gaming, C5 OLED 65 or C5 OLED 77?+
C5 OLED 65 offers 144Hz refresh and 4 HDMI 2.1 ports.
Does C5 OLED 65 or C5 OLED 77 support Dolby Vision?+
Both support Dolby Vision.