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Head to head · Prices checked Nov 11, 2026

MMD KM40 vs NIUNIU Roly poly 40 R3

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What actually differs

The differences that matter

Skip the 40-row spec sheet. These are the specs that change how each board feels, sounds, and fits your desk.

MMD KM40

NIUNIU Roly poly 40 R3

  • Switch options

    Linear, Tactile

    Linear

  • Mount style

    Gasket Mount

    Top Mount

  • QMK

    Yes

    No

    The deep option when you want to remap every key

  • VIA

    Yes

    No

    GUI remapping without compiling firmware

  • Sound dampening

    Yes

    No

KeebFinder scores

How we score
  • MMD KM40
  • NIUNIU Roly poly 40 R3
Performance
60
47
Build quality
82
74
Productivity
69
51
Customizability
83
70
Portability
84
80

What they share

  • Layout size: 40%
  • Connection: Bluetooth, 2.4 GHz, Wired
  • Hot-swappable
  • Case material: Aluminum
See every spec side by side

Full specs

MMD KM40 vs NIUNIU Roly poly 40 R3 specs

Every tracked spec, side by side. Rows marked with a dot differ between the boards.

10 of 21 specs differ

MMD KM40

NIUNIU Roly poly 40 R3

Typing & switches

Switch options

Linear, Tactile
Linear

Hot-swappable

Yes
Yes

Mount style

Gasket Mount
Top Mount

Sound dampening

Yes
No

Layout

Layout size

40%
40%

Layout standard

ANSI
ANSI

Ergonomics

Standard
Standard

Display

None
None

Connectivity & battery

Connection

Bluetooth, 2.4 GHz, Wired
Bluetooth, 2.4 GHz, Wired

Battery

2,000 mAh
—

USB-C

Yes
No

Build & materials

Case material

Aluminum
Aluminum

Plate material

Polycarbonate
FR4

Keycaps

PBT
—

Weight

620 g
—

Typing angle

—
9°

Backlight

RGB
None

Firmware & software

QMK

Yes
No

VIA

Yes
No

VIAL

No
Yes

Extras

Released

2026
2025

Where to buy

Compare prices

Live prices from the stores we track, cheapest in-stock offer first.

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MMD KM402 stores

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