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Head to head · Prices checked Nov 11, 2026

Mechboards NIBBLE vs Redragon CASTOR K631 Pro SE

Get the Mechboards NIBBLE for knob and qmk. Get the Redragon CASTOR K631 Pro SE for hot-swappable.

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Quick verdict

Which one should you get?

Get the

Mechboards NIBBLE

Knob

Build quality in the top 40% of 65% boards under $100.

Rules this board out

  • Switches are soldered. Swapping them means soldering.

Get the

Redragon CASTOR K631 Pro SE

Hot-swappable

Build quality in the bottom 25% of 65% boards under $100.

Rules this board out

  • No ISO layout. ISO-DE, UK, and other ISO variants are not offered.

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.

Mechboards NIBBLE

Redragon CASTOR K631 Pro SE

  • Hot-swappable

    No

    Yes

    Switch changes without soldering

  • Case material

    Acrylic, Plastic

    Plastic

  • Mount style

    PCB Mount

    Bottom Mount

  • Knob

    Yes

    No

  • QMK

    Yes

    No

    The deep option when you want to remap every key

KeebFinder scores

How we score
  • Mechboards NIBBLE
  • Redragon CASTOR K631 Pro SE
Performance
53
70
Build quality
70
51
Productivity
53
49
Customizability
77
56
Portability
59
83

What they share

  • Layout size: 65%
See every spec side by side

Full specs

Mechboards NIBBLE vs Redragon CASTOR K631 Pro SE specs

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

10 of 21 specs differ

Mechboards NIBBLE

Redragon CASTOR K631 Pro SE

Typing & switches

Switch options

—
Clicky, Linear

Hot-swappable

No
Yes

Mount style

PCB Mount
Bottom Mount

Screw-in stabilizers

Yes
No

Layout

Layout size

65%
65%

Layout standard

ANSI, ISO
ANSI

Ergonomics

Standard
Standard

Knob

Yes
No

Display

None
None

Connectivity & battery

Connection

—
Bluetooth, 2.4 GHz, Wired

Battery

—
1,600 mAh

USB-C

No
Yes

Build & materials

Case material

Acrylic, Plastic
Plastic

Plate material

FR4
—

Keycaps

—
ABS

Weight

—
470 g

Dimensions

—
40 x 309 x 104 mm

Backlight

RGB
RGB

Firmware & software

QMK

Yes
No

N-key rollover

No
Yes

Extras

Released

2021
2023

For EU buyers

ISO layouts by store

Which stores sell ISO-DE, UK, and the other regional layouts.

Mechboards NIBBLE

Listed on the product, not split by store: ISO.

Redragon CASTOR K631 Pro SE

No ISO layout at the stores we track.

Where to buy

Compare prices

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

Prices in USD are converted to your currency and can change at any time. KeebFinder may earn a commission when you buy through these links, at no extra cost to you.

Lowest price across stores, Amazon excluded.

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