A Hall effect keyboard puts a small magnet in the stem of every switch and a magnetic sensor under it on the circuit board. The sensor reads how close the magnet is, so the keyboard knows how far down each key is, not only whether it is pressed.
We have not had these keyboards on our desks for this guide. The features and figures below come from the makers’ own product pages and help articles, checked on October 16, 2026. The two makers we quote are Wooting and Keychron, because both publish their numbers in plain text.
How a Hall effect switch works
A classic mechanical switch registers a press when two metal contacts touch. That happens at one fixed point in the key’s travel, and the key resets at another fixed point on the way up. Keychron puts the difference this way: “Unlike mechanical switches, which depend on physical contact, magnetic switches use magnets to detect key presses.”
Wooting’s explainer describes the rest. The sensor measures the effect of the magnet’s field on a current running through it. Move the magnet closer and the signal gets stronger; move it away and it drops. Put the magnet on the switch stem and the sensor on the board below, and the keyboard can follow the key through its whole travel. There is no physical connection between the switch and the sensor, which is why Wooting’s switches can be hot-swappable.
The idea is old. Wooting dates the first Hall effect keyboard switches to 1968, built from large Micro Switch parts made by Honeywell. Today the sensors are cheap, and the maker’s firmware smooths their signal into usable data. Wooting notes that the position of the magnet and the calibration between magnet and sensor “greatly influence the result”.
Hall effect, HE, magnetic, TMR
Shops use these names loosely. Keychron’s K2 HE page calls its switches “Magnetic Hall Effect switches” in one line and, further down, says each key has a dedicated TMR (tunneling magnetoresistance) sensor. Both are forms of magnetic sensing that measure depth. When you compare boards, the label matters less than the numbers the maker publishes for actuation and reset.
What the magnet makes possible
Adjustable actuation
You choose how deep a key has to go before it counts as pressed, per key. The ranges differ by maker:
| Keyboard | Actuation point | Step |
|---|---|---|
| Wooting 80HE | Presets of 0.1, 0.5, 1, 2, 3 or 4 mm | 0.1 mm precision |
| Keychron K2 HE | 0.2 to 3.8 mm | 0.1 mm |
A shallow point suits fast games. A deeper one cuts accidental presses when you type, which is the trade-off Keychron describes on its K2 HE page.
Rapid Trigger
On a normal switch, a key resets only when it rises past its fixed reset point. With Rapid Trigger, the keyboard watches the direction the key moves. As soon as the key starts to come up by a set distance, it resets; push it down again and it fires again. Wooting, which calls Rapid Trigger its own invention, explains it in its help center: the feature works only past the actuation point you set, and a second setting, Rapid Trigger sensitivity, controls how far the key has to rise before it resets.
Wooting also has Continuous Rapid Trigger, which keeps the feature active until the key is fully released instead of cancelling it above the actuation point. Keychron describes its version as “press to activate, release to reset”.
Analog input
Because the keyboard knows the depth of each key, it can send a range of values instead of on or off. Wooting’s Controller Input mode turns the WASD keys into something closer to a gamepad stick: in a racing game you can feather the throttle, and in a sandbox game you can walk at any speed between a crawl and a run. Wooting also publishes an open-source Analog SDK so other software can read the depth of each key.
Several actions on one key
Wooting’s Dynamic Keystroke (DKS) assigns different actions to a half press, a full press and the release of the same key. Mod Tap gives a key one action when you tap it and another when you hold it.
Opposite keys: SOCD features
When you press left and right strafe together, one of them has to win. Wooting’s Snappy Tappy lets you choose the rule, for example the key pressed last. Its Rappy Snappy keeps the key pressed deeper. Keychron has Last Key Priority (LKP) and Snap Click, where the deeper press takes precedence. Gamers call this group SOCD, short for simultaneous opposing cardinal directions.
Check the game’s rules first
Some of these features are not allowed everywhere. On August 19, 2024, Valve posted “Side-stepping Skill” for Counter-Strike 2. It says Valve will no longer allow “automation (via scripting or hardware)” that gets around core skills, and that on Valve Official Servers, players suspected of “automating multiple player actions from a single game input may be kicked from their match”. The post tells owners of a keyboard with an input-automation feature, giving “Snap Tap Mode” as its example, to switch it off before they join a match.
Valve’s post does not mention Rapid Trigger or adjustable actuation by name. If your board has an SOCD feature, switch it off for Counter-Strike 2 on Valve’s servers, and read the rules of any other game, league or community server before you use it there.
Switches are not universal
A magnetic board reads a magnet that its sensor is calibrated for, so you cannot drop just any magnetic switch into it. Keychron is explicit. The K2 HE with Gateron Double-Rail Magnetic Nebula switches version 1 “supports only Gateron Double-Rail Magnetic Switches”, and the page names Gateron Magnetic Jade and KS-20 as not supported. Version 2 supports Keychron’s Ultra-Fast Lime Magnetic switches.
Before you buy replacement switches, find the compatibility list on your keyboard maker’s page. Do not go by the word “magnetic” on the switch box.
When keys fire on their own
A very shallow actuation point has a side effect. Wooting’s help center lists switch plate flex as one cause of nearby keys activating together: if the plate bends, neighbouring switches move, and whether that registers depends on your actuation and Rapid Trigger settings. It also lists macro software and leftover DKS bindings. Its checks are to remove any tape mod, press on a switch housing while you watch the Analog Monitor in Wootility, and go back to a stock plate if you changed it.
Pros
- Actuation point set per key, down to 0.1 or 0.2 mm on the boards above
- Rapid Trigger resets a key as soon as it starts to rise
- Analog movement on WASD, like a gamepad stick
- No contacts touching inside the switch
Cons
- Only switches on the maker’s compatibility list work
- SOCD features are not allowed on Counter-Strike 2’s official servers
- Very shallow settings can turn plate flex into stray presses
What to check on a product page
- Actuation range and step. Look for both ends of the range and the step size, as Keychron lists them.
- Rapid Trigger settings. Check that you can set the sensitivity, and per key if that matters to you.
- SOCD switch. If the board has Snap Tap-style features, check that you can turn them off.
- Switch compatibility. Find the list of switches the board accepts.
- Software. Wooting’s Wootility runs in an app or in the browser and stores up to four profiles on the keyboard. Keychron’s K2 HE runs QMK open-source firmware.
- Polling rate. Wooting lists true 8 kHz polling for the 80HE; Keychron lists 1000 Hz for the K2 HE in wired and 2.4 GHz modes.