Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Logitech - G309 Lightspeed | Logitech - MX Master 4 |
|---|---|---|
| Polling rate | 1000 Hz | 125 Hz |
| Battery | 300 h | 1680 h |
| Max DPI | 25600 | 8000 |
| Weight | 68 g | 150 g |
| Buttons | 6 | 7 |
Between the G309 Lightspeed and MX Master 4, the G309 Lightspeed comes out ahead in polling rate / max dpi, while the MX Master 4 wins on battery / buttons. Overall, the G309 Lightspeed scores 63.1 and the MX Master 4 scores 50.9 on our Mars Score.
Which should you buy?
The G309 Lightspeed is the clear pick on raw spec strength, leading by 12.2 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the G309 Lightspeed if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are polling rate, max dpi, weight. The single most decisive one: Polling rate — 700.00% more. 1000 Hz vs 125 Hz.
Pick the MX Master 4 if you care most about battery / buttons. Its strongest claims are battery, buttons. The single most decisive one: Battery — 460.00% more. 1680 h vs 300 h.
Both ship with comparable wireless, so those specs do not separate the two — focus on the differences below.
Bottom line: the G309 Lightspeed is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Logitech - G309 Lightspeed or Logitech - MX Master 4?
Logitech - G309 Lightspeed leads the current Mars Score by 12.2 points.The more useful decision is the trade-off behind that result: compare max dpi, polling rate, weight against the way you will actually use the product.
Choose Logitech - G309 Lightspeed if…
Logitech - G309 Lightspeed has the measurable edge on polling rate hz, max dpi, weight g.
Choose Logitech - MX Master 4 if…
Logitech - MX Master 4 has the measurable edge on battery h, button count.
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 Logitech - G309 Lightspeed wins
- ▲Polling rate — 700.00% more. 1000 Hz vs 125 Hz.
- ▲Max DPI — 220.00% more. 25600 vs 8000.
- ▲Weight — 82.00 g less. 68 vs 150.
Why Logitech - MX Master 4 wins
- ▲Battery — 460.00% more. 1680 h vs 300 h.
- ▲Buttons — 1.00 more. 7 vs 6.
Spec comparison
Sensor
| Spec | Logitech - G309 Lightspeed | Logitech - MX Master 4 |
|---|---|---|
| Max DPI | 25600lead | 8000 |
| Max IPS | 400lead | 0 |
| Polling rate | 1000 Hzlead | 125 Hz |
Design
| Spec | Logitech - G309 Lightspeed | Logitech - MX Master 4 |
|---|---|---|
| Weight | 68 glead | 150 g |
| Buttons | 6 | 7lead |
| Shape | Right-handed | Right-handed |
Connectivity
| Spec | Logitech - G309 Lightspeed | Logitech - MX Master 4 |
|---|---|---|
| Wireless | true | true |
| Battery | 300 h | 1680 hlead |