KiiBoom Phantom 21 Crystal Acrylic Numpad - Compact Triple-Mode

In this review the KiiBoom Phantom 21 comes across as a finely tuned tool for anyone who needs a dedicated numeric keypad that is compact, customizable, and built to last. With 21 keys, a multi-function control knob, and triple-mode connectivity (Bluetooth 5.0, 2.4 GHz dongle, and wired USB-C), the Phantom 21 is best for professionals and power users who move between workstations or prefer a separate numeric block. The single biggest reason to buy is its blend of tactile build quality and flexibility: it pairs a durable brushed metal feel and pleasant acoustics with deep software customization and reliable multi-OS support.

Key Features

• Compact 21-key layout: Places a full set of numeric and editing keys in a small footprint so data entry and numeric tasks stay efficient on crowded desks.
• Triple-mode connectivity: Switch seamlessly between Bluetooth 5.0, 2.4 GHz wireless, and wired USB-C to match office, travel, or gaming setups.
• Hot-swappable switches: Lets users change mechanical switches without soldering, enabling sound and feel customization over time.
• Multi-function control knob: Provides tactile volume, scroll, or zoom control and can be remapped for creative workflows.
• South-facing RGB with acrylic case: Delivers vivid backlighting and a clear aesthetic that showcases custom lighting while maintaining keycap compatibility.
• KiiBOOM customization software: Enables macros, key remaps, and multiple profiles so complex tasks can be reduced to single keypresses.

Who It's For

The Phantom 21 is ideal for financial analysts, data-entry professionals, and content creators who need a dedicated numeric block with high customization and a robust build. Its travel-friendly footprint and versatile connectivity also make it a smart choice for people who move between desktop and laptop setups or who frequently present from different machines.

Users who want a full-sized keyboard with an integrated numpad or those who need ultra-compact one-handed macro pads should look elsewhere; this device is designed specifically as a standalone numeric keypad rather than a replacement for a full keyboard.

Pros & Cons

Pros

• Solid, weighty build and pleasing acoustics that feel premium during use.
• Flexible connectivity options give dependable pairing at home, office, or on the go.
• Deep customization with hot-swap support and software for macros and profiles.
• Control knob adds useful physical control for volume, scrolling, or custom actions.

Cons

• As a focused numeric pad it lacks keys found on full keyboards, so it is an accessory rather than a standalone typing solution.
• Customization requires the vendor software, which could be a minor setup step for some users.

Specifications

Our Verdict

The KiiBoom Phantom 21 is a practical, well-built numeric keypad that delivers strong value for users who need dedicated numeric input, customizable macros, and flexible connectivity. Its solid construction, satisfying typing sound, and programmable knob make it a worthwhile addition for professionals and enthusiasts seeking a compact, travel-friendly numeric solution.

Frequently Asked Questions

Does it work with both Windows and Mac?
Yes; the Phantom 21 is designed to integrate with Windows, Mac, and Linux systems and supports profile switching.

Can the switches be replaced?
Yes; the keypad supports hot-swappable mechanical switches so users can change switch types without soldering.

What connectivity options are available?
It supports Bluetooth 5.0, a 2.4 GHz wireless dongle, and a wired USB-C connection for flexible use.