Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | TCL - C855 Mini LED 65 | TCL - QM851 Mini LED 75 |
|---|---|---|
| Peak brightness | 3500 nits | 5000 nits |
| Screen size | 65 " | 75 " |
Between the C855 Mini LED 65 and QM851 Mini LED 75, the C855 Mini LED 65 comes out ahead in several specs, while the QM851 Mini LED 75 wins on peak brightness / screen size. Overall, the C855 Mini LED 65 scores 74.3 and the QM851 Mini LED 75 scores 78.2 on our Mars Score.
Which should you buy?
The QM851 Mini LED 75 edges ahead on the Mars Score (74.3 vs 78.2), but the 3.9-point gap is small enough that the right pick comes down to which spec advantages matter to you.
The C855 Mini LED 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 QM851 Mini LED 75 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 peak brightness, screen size. The single most decisive one: Peak brightness — 42.86% more. 5000 nits vs 3500 nits.
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: TCL - C855 Mini LED 65 or TCL - QM851 Mini LED 75?
TCL - QM851 Mini LED 75 leads the current Mars Score by 3.9 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 TCL - C855 Mini LED 65 if…
TCL - C855 Mini LED 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 TCL - QM851 Mini LED 75 if…
TCL - QM851 Mini LED 75 has the measurable edge on peak brightness nits, 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 TCL - C855 Mini LED 65 wins
- No decisive advantages.
Why TCL - QM851 Mini LED 75 wins
- ▲Peak brightness — 42.86% more. 5000 nits vs 3500 nits.
- ▲Screen size — 15.38% more. 75 " vs 65 ".
Spec comparison
Display
| Spec | TCL - C855 Mini LED 65 | TCL - QM851 Mini LED 75 |
|---|---|---|
| Screen size | 65 " | 75 "lead |
| Panel typeⓘ | Mini-LED | Mini-LED |
| Resolutionⓘ | 4K | 4K |
| Refresh rateⓘ | 144 Hz | 144 Hz |
| Peak brightnessⓘ | 3500 nits | 5000 nitslead |
HDR & Smart
| Spec | TCL - C855 Mini LED 65 | TCL - QM851 Mini LED 75 |
|---|---|---|
| Dolby Visionⓘ | true | true |
| HDR10+ⓘ | true | true |
| Smart OS | Google TV | Google TV |
| Dolby Atmosⓘ | true | true |
Gaming
| Spec | TCL - C855 Mini LED 65 | TCL - QM851 Mini LED 75 |
|---|---|---|
| HDMI 2.1 portsⓘ | 2 | 2 |
| VRRⓘ | true | true |
| ALLM | true | true |
Frequently asked
Which is brighter, C855 Mini LED 65 or QM851 Mini LED 75?+
QM851 Mini LED 75 peaks at 5000 nits vs 3500 nits.
Which is better for gaming, C855 Mini LED 65 or QM851 Mini LED 75?+
C855 Mini LED 65 offers 144Hz refresh and 2 HDMI 2.1 ports.
Does C855 Mini LED 65 or QM851 Mini LED 75 support Dolby Vision?+
Both support Dolby Vision.