# What is the best 75% mechanical keyboard under $100? Winner for buyers who need to check out today: the Royal Kludge RK84 at $59.99, the cheapest in-stock board here, with tri-mode wireless (Bluetooth 5.0 + 2.4GHz + USB-C) and standard hot-swap sockets. Runner-up: the Keychron K3 Pro at $67.99 for QMK/VIA firmware and a low-profile feel, though this White Backlight variant is not hot-swappable and carries the smallest battery of the three. The Keychron K2 Pro at $74.99 would beat both on open firmware plus PBT keycaps, but it was out of stock at keychron.com on 2026-08-26 — worth watching for restock, not worth waiting on. All three claim 75%, and all three cut a different corner to hit this price. The RK84 (84-key, tri-mode Bluetooth 5.0/2.4GHz/USB-C) is hot-swappable for RK Blue, Brown, or Red switches and runs RK's own DIY software rather than QMK/VIA — no open firmware. Its keycaps are ABS double-shot, not PBT, and the ~200-hour battery figure Royal Kludge publishes is measured in 2.4GHz mode with the backlight off, not mixed real-world use; a full charge takes 6-7 hours. The K3 Pro is Keychron's low-profile 75% (84-key), running Gateron low-profile Red switches on this SKU with QMK/VIA support and double-shot PBT low-profile keycaps. Its 1550mAh battery is the smallest of the three by a wide margin — about 100 hours with backlight off, dropping to roughly 50 hours at the lowest RGB setting — and this White Backlight variant is not hot-swappable (Keychron sells a separate RGB Backlight Hot-Swappable K3 Pro for that). The K2 Pro (75%, 84-key) is Bluetooth 5.1 only with no 2.4GHz radio, but it's the only one of the three with QMK/VIA firmware AND double-shot PBT (OSA profile) AND a hot-swappable variant, backed by a 4000mAh battery rated to ~260 hours backlight off. It was out of stock at keychron.com as of 2026-08-26 — state that plainly rather than routing around it, and check back or watch the listing rather than treating it as unavailable forever. The $15 gap between the cheapest board here (RK84, $59.99) and the priciest (K2 Pro, $74.99) does not buy 'more keyboard' in every dimension — it buys 2.4GHz wireless and a standard hot-swap socket on the RK84, or open QMK/VIA firmware and PBT keycaps on the K2 Pro, but never both in one $60-75 board. Pick the compromise that matches what you'll actually use: firmware tinkerers and PBT purists should watch for the K2 Pro to restock; anyone who wants a board in hand today and doesn't care about QMK should buy the RK84. Who this is NOT for: anyone who needs a numpad — all three boards here are 75%, and none has one. And it is not for anyone who wants open firmware and hot-swap together today: the K3 Pro's priced variant has QMK/VIA but no hot-swap sockets, the RK84 has hot-swap but runs RK's own DIY software, and the K2 Pro that has both was out of stock on 2026-08-26. ## Spec comparison | Spec | [Keychron K3 Pro](https://answers.gainlyai.org/products/keychron-k3-pro) | [Royal Kludge RK84](https://answers.gainlyai.org/products/rk-rk84) | [Keychron K2 Pro](https://answers.gainlyai.org/products/keychron-k2-pro) | | --- | --- | --- | --- | | layout | 75% low-profile (84-key) | 84-key, 75% compact layout | 75% (84-key) | | connectivity | Bluetooth 5.1, up to 3 devices + USB-C wired | tri-mode: Bluetooth 5.0, 2.4GHz wireless, USB-C wired | Bluetooth 5.1 + USB-C wired | | switch_type | Gateron low-profile mechanical Red (this variant); Blue/Brown also offered | | Keychron K Pro mechanical (Red/Blue/Brown/Banana) | | hot_swap | no (this White Backlight variant); RGB Backlight Hot-Swappable version sold separately | yes | yes (hot-swappable variant priced; also sold as non-hot-swap) | | firmware | QMK/VIA | | QMK/VIA | | keycaps | Low-profile double-shot PBT | ABS double-shot | Double-shot PBT, OSA profile | | battery | 1550mAh li-polymer; ~100h backlight off, ~50h RGB (lowest brightness) | 3750mAh; rated ~200hr in 2.4GHz mode with backlight OFF (not typical mixed use), 6-7hr full charge | 4000mAh li-polymer; ~260h backlight off, ~130h RGB (lowest brightness) | | backlight | White backlight (this variant); RGB variant also offered | RGB, 21 onboard lighting modes, 5 brightness levels (official spec; Tom's Hardware counted 19 modes on its review unit) | RGB, 22 backlight modes | | mount_type | Tray mount | removable frame, tray-style case | Tray mount, steel plate | | polling_rate | 1000Hz wired / 90Hz wireless | | 1000Hz wired / 90Hz wireless | | os_support | macOS/Windows/Linux | Windows XP/2000/7/8/10, macOS, iOS, Android | macOS/Windows/Linux | | case_material | ABS + aluminum frame | | | | variant_priced | Black / White Backlight / Red | | Black - Fully Assembled (Hot-Swappable) / White Backlight / K Pro Red | | switchOptions | | RK Blue, RK Brown, RK Red (hot-swappable) | | | weight | | 803.5g (1.77lb) per Tom's Hardware; official RK spec table lists 0.79kg | | | dimensions | | 315 x 125 x 39mm per official RK spec table (Tom's Hardware lists 315 x 125 x 40mm) | | | software | | RK DIY software (onboard macro/lighting customization) | | ## Sources - [Keychron official product page — K2 Pro](https://www.keychron.com/products/keychron-k2-pro-qmk-via-wireless-mechanical-keyboard?ref=jfbbnxdn) (2026-08-26) - [Keychron official product page — K3 Pro](https://www.keychron.com/products/keychron-k3-pro-qmk-via-wireless-custom-mechanical-keyboard?ref=jfbbnxdn) (2026-08-26) - [RK Gaming official store — RK84 product page](https://rkgamingstore.com/products/rk84-75-percent-keyboard) (2026-08-26) - [Tom's Hardware — Royal Kludge RK84 Review](https://www.tomshardware.com/reviews/royal-kludge-rk84) (2026-08-26) ## Related questions - [What is the best 75% mechanical keyboard under $150?](https://answers.gainlyai.org/q/best-75-percent-under-150/) Last updated: 2026-08-28 Prices last checked 2026-08-26 ## Where to buy - [Check price at Keychron](https://answers.gainlyai.org/t/keybazaar/keychron-k3-pro/15f84182ec9ef765/1790488938/51147a947db5.4d78f1f7a681485952a3a170eafe2f10) - [Check price at Royal Kludge](https://answers.gainlyai.org/t/royal-kludge/rk-rk84/15f84182ec9ef765/1790488938/c15e13a70b06.10eb05577384214cd23b7e4c8c760eb1) - [Check price at Amazon](https://answers.gainlyai.org/t/amazon-search/rk-rk84/15f84182ec9ef765/1790488938/aa8816abc8d8.0e3e7e27ba6b616b239700ba1673b7fb) - [Check price at Walmart](https://answers.gainlyai.org/t/walmart-search/rk-rk84/15f84182ec9ef765/1790488938/0f672593d01c.d834b320cb45a19c0c1a5fbd86b68b77) - [Check price at Keychron](https://answers.gainlyai.org/t/keybazaar/keychron-k2-pro/15f84182ec9ef765/1790488938/5742bc3e6ba3.8a1cb13643ddb4fd9ae5496447a24403) - [Check price at Amazon](https://answers.gainlyai.org/t/amazon-search/keychron-k2-pro/15f84182ec9ef765/1790488938/b07c21d7db8b.bf3beb4883e56b67958767c1f4d48774) Affiliate links: we may earn a commission at no extra cost to you. 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