Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | LG - C5 OLED 55 | TCL - QM751 Mini LED 65 |
|---|---|---|
| Peak brightness | 1300 nits | 3000 nits |
| Refresh rate | 144 Hz | 120 Hz |
| Screen size | 55 " | 65 " |
| HDMI 2.1 ports | 4 | 2 |
| Panel type | OLED | Mini-LED |
| Smart OS | webOS | Google TV |
Between the C5 OLED 55 and QM751 Mini LED 65, the C5 OLED 55 comes out ahead in refresh rate / hdmi 2.1 ports, while the QM751 Mini LED 65 wins on peak brightness / screen size. Overall, the C5 OLED 55 scores 66.8 and the QM751 Mini LED 65 scores 70.6 on our Mars Score.
Which should you buy?
The QM751 Mini LED 65 edges ahead on the Mars Score (66.8 vs 70.6), but the 3.8-point gap is small enough that the right pick comes down to which spec advantages matter to you.
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 refresh rate, hdmi 2.1 ports, panel type. The single most decisive one: Refresh rate — 20.00% more. 144 Hz vs 120 Hz.
Pick the QM751 Mini LED 65 if you care most about peak brightness / screen size. Its strongest claims are peak brightness, screen size, smart os. The single most decisive one: Peak brightness — 130.77% more. 3000 nits vs 1300 nits.
Both ship with comparable dolby vision, vrr, 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 TCL - QM751 Mini LED 65?
TCL - QM751 Mini LED 65 leads the current Mars Score by 3.8 points.The more useful decision is the trade-off behind that result: compare screen size, panel type, refresh rate, hdmi 2.1 ports against the way you will actually use the product.
Choose LG - C5 OLED 55 if…
LG - C5 OLED 55 has the measurable edge on refresh rate hz, hdmi 2 1 count, panel type.
Choose TCL - QM751 Mini LED 65 if…
TCL - QM751 Mini LED 65 has the measurable edge on peak brightness nits, screen size in, smart os.
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
- ▲Refresh rate — 20.00% more. 144 Hz vs 120 Hz.
- ▲HDMI 2.1 ports — 2.00 more. 4 vs 2.
- ▲Panel type: OLED (vs Mini-LED).
Why TCL - QM751 Mini LED 65 wins
- ▲Peak brightness — 130.77% more. 3000 nits vs 1300 nits.
- ▲Screen size — 18.18% more. 65 " vs 55 ".
- ▲Smart OS: Google TV (vs webOS).
Spec comparison
Display
| Spec | LG - C5 OLED 55 | TCL - QM751 Mini LED 65 |
|---|---|---|
| Screen size | 55 " | 65 "lead |
| Panel typeⓘ | OLEDlead | Mini-LED |
| Resolutionⓘ | 4K | 4K |
| Refresh rateⓘ | 144 Hzlead | 120 Hz |
| Peak brightnessⓘ | 1300 nits | 3000 nitslead |
HDR & Smart
| Spec | LG - C5 OLED 55 | TCL - QM751 Mini LED 65 |
|---|---|---|
| Dolby Visionⓘ | true | true |
| HDR10+ⓘ | false | truelead |
| Smart OS | webOS | Google TVlead |
| Dolby Atmosⓘ | true | true |
Gaming
| Spec | LG - C5 OLED 55 | TCL - QM751 Mini LED 65 |
|---|---|---|
| HDMI 2.1 portsⓘ | 4lead | 2 |
| VRRⓘ | true | true |
| ALLM | true | true |
Frequently asked
Which is brighter, C5 OLED 55 or QM751 Mini LED 65?+
QM751 Mini LED 65 peaks at 3000 nits vs 1300 nits.
Which is better for gaming, C5 OLED 55 or QM751 Mini LED 65?+
C5 OLED 55 offers 144Hz refresh and 4 HDMI 2.1 ports.
Does C5 OLED 55 or QM751 Mini LED 65 support Dolby Vision?+
Both support Dolby Vision.