Nintendo Switch serial number checker and a complete RCM guide. In seconds you know whether your Switch is patched or RCM-compatible, and therefore whether an Atmosphère patch is possible — after that, it is all about preparing the microSD.
RCM — unpatched V1 units
Early Switch units (built before mid-2018) have a hardware boot flaw (RCM mode): a jig and an injector are enough to launch a custom firmware. Check the serial number — it cannot be fixed by a system update.
Modchip — V2, Lite, OLED
Newer models require a chip soldered onto the mainboard. Great practice for fine soldering, but the operation stays delicate and voids the warranty.
Atmosphère & homebrew
The reference CFW: interface themes, retro emulators, light overclocking, archival save backups. All on your own consoles and your own games.
Is my Switch patched?
Select the prefix of your serial number (or paste the full serial)
Enter the 10 digits that follow the prefix
0 / 10 digits
A serial number is never a 100 % guarantee: it is an estimate based on manufacturing dates collected by the community. Only a real RCM test settles it for good.
Where do I find my serial number?
On the sticker underneath the console (or in the kickstand on the OLED model), or in System Settings → System → Serial Information. It always starts with a 3 or 4 character prefix followed by 10 digits. Read carefully: 0 looks like the letter O, 1 looks like the letter I — only digits follow the prefix.
Prefix
Not patched
Possibly patched
Patched
How do I read this table?
Not patched: consoles built before the factory fix — the RCM exploit is present, the estimate is very reliable. Possibly patched (grey area): the mid-2018 transition period, where fixed and unfixed batches are mixed within the same serial ranges — no conclusion is possible without a test. Patched: the fix is in place, and that is final.
Bounds are compared over the full 10 digits that follow the prefix. A system update changes nothing: the fix is burned into the chip at the factory, and it cannot be removed either.
How does it work?
Early Switch units have a hardware boot flaw (RCM mode) that allows unsigned code to run. In mid-2018 Nintendo fixed the Tegra chip at the factory: impossible to undo with an update. The “Mariko” generation (2019 Switch, Lite, OLED) closes the flaw in hardware — only a soldered chip enables modding there.
Full guide: testing RCM on a grey-area console
What you need
An RCM jig (a few euros) that bridges pin 10 of the right Joy-Con rail to ground (pins 1, 7 or 9). Avoid the paperclip trick: badly placed, it can damage the console.
A USB-C cable to a PC and the TegraRcmGUI software (Windows).
The hekate payload: the hekate_ctcaer_X.X.X.bin file from the official hekate archive.
Test steps
Fully power off the console (hold Power → Power Options → Turn Off — not sleep mode).
Remove the right Joy-Con and slide the jig all the way down the rail.
Hold Volume + then press Power. If the screen stays completely black (no Nintendo logo), you are in RCM.
Connect the console to the PC over USB-C. In TegraRcmGUI: Settings tab → Install Driver. If that fails, use Zadig: device “APX” → driver libusbK.
The hekate interface appears → console not patched: the RCM exploit works, a jig is all you need for the whole setup.
The injector reports 0 / 0x0000 bytes sent → console patched, final. A soldered modchip (HWFLY, RP2040) is required — no software method exists.
Black screen but bytes were sent → corrupted payload: re-download hekate and try again before concluding.
Why the test can fail on a compatible console
Console asleep instead of off → it boots normally with the Nintendo logo: power it off fully from the power menu.
Jig not fully inserted → the console boots normally: push the jig all the way in and start over.
Charge-only USB cable → no device shows up on the PC: use a USB-C data cable (from a drive, or a phone in file-transfer mode).
Missing APX driver → unknown device in Device Manager: install the driver via TegraRcmGUI, otherwise Zadig → “APX” → libusbK.
Fussy PC USB port → try a USB 2.0 port directly, without a hub.
Until each of these points is ruled out, a failure does not mean “patched console”.
After the test
Not patched → everything is done in software: jig + hekate injection at each boot, Atmosphère on the microSD, emuMMC recommended to isolate the original system.
Patched → only a soldered chip (modchip) works: fine soldering on the mainboard, a real risk of permanent damage, hardware and labour costs. It is not reversible without traces.
In every case → any modified console risks a permanent ban from Nintendo online services. Never mix a modified system with an online account you care about.
Precautions
This test writes nothing to the console: no brick risk.
Do not enable AutoRCM without understanding it: the console no longer boots on its own, charges very slowly once drained, and the procedure is risky on Mariko hardware.