Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | LG - C5 OLED 55 | LG - C4 OLED 65 |
|---|---|---|
| Peak brightness | 1300 nits | 1000 nits |
| Screen size | 55 " | 65 " |
Between the C5 OLED 55 and C4 OLED 65, the C5 OLED 55 comes out ahead in peak brightness, while the C4 OLED 65 wins on screen size. Overall, the C5 OLED 55 scores 66.8 and the C4 OLED 65 scores 67.8 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (66.8 vs 67.8). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
Pick the C5 OLED 55 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. The biggest gaps in its favor are peak brightness. The single most decisive one: Peak brightness — 30.00% more. 1300 nits vs 1000 nits.
Pick the C4 OLED 65 if you care most about screen size. Its strongest claims are screen size. The single most decisive one: Screen size — 18.18% more. 65 " vs 55 ".
Both ship with comparable panel type, refresh rate, dolby vision, 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 55 or LG - C4 OLED 65?
LG - C4 OLED 65 leads the current Mars Score by 1.0 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 55 if…
LG - C5 OLED 55 has the measurable edge on peak brightness nits.
Choose LG - C4 OLED 65 if…
LG - C4 OLED 65 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 55 wins
- ▲Peak brightness — 30.00% more. 1300 nits vs 1000 nits.
Why LG - C4 OLED 65 wins
- ▲Screen size — 18.18% more. 65 " vs 55 ".
Spec comparison
Display
| Spec | LG - C5 OLED 55 | LG - C4 OLED 65 |
|---|---|---|
| Screen size | 55 " | 65 "lead |
| Panel typeⓘ | OLED | OLED |
| Resolutionⓘ | 4K | 4K |
| Refresh rateⓘ | 144 Hz | 144 Hz |
| Peak brightnessⓘ | 1300 nitslead | 1000 nits |
HDR & Smart
| Spec | LG - C5 OLED 55 | LG - C4 OLED 65 |
|---|---|---|
| Dolby Visionⓘ | true | true |
| HDR10+ⓘ | false | false |
| Smart OS | webOS | webOS |
| Dolby Atmosⓘ | true | true |
Gaming
| Spec | LG - C5 OLED 55 | LG - C4 OLED 65 |
|---|---|---|
| HDMI 2.1 portsⓘ | 4 | 4 |
| VRRⓘ | true | true |
| ALLM | true | true |
Frequently asked
Which is brighter, C5 OLED 55 or C4 OLED 65?+
C5 OLED 55 peaks at 1300 nits vs 1000 nits.
Which is better for gaming, C5 OLED 55 or C4 OLED 65?+
C5 OLED 55 offers 144Hz refresh and 4 HDMI 2.1 ports.
Does C5 OLED 55 or C4 OLED 65 support Dolby Vision?+
Both support Dolby Vision.