Tamper Check

An implant board adds weight. Weigh your Ledger on a 0.001 g scale and type the numbers. Nothing leaves your browser.

1 · Weigh it 3 times

Tare the empty scale to 0.000 g, place the wallet, note the reading. Repeat 3 times.

Reading 1 (g)Reading 2 (g)Reading 3 (g)

Reference weights are examples. For a real check, weigh a unit bought direct from ledger.com on the same scale.

2 · Find where the extra mass is (two scales + a ruler)

1. Two scales side by side, a rigid ruler across both. Tare both to 0.000.

2. Put the wallet exactly on the ruler's middle mark.

3. Read Left and Right.

4. Rotate it 180° on the spot. Read Left and Right again.

Left (g)Right (g)Left after 180° (g)Right after 180° (g)Distance between scale centres (mm)

How we judge

Thresholds for the selected model (Ledger Flex (EXAMPLE values)). All numbers are examples.

Measurement	Result	Confidence
Weight Δ within ±0.050 g	Normal	Medium (High if CoM is also centred)
Weight Δ > 0.050 g	Slightly heavy: suspicious	Low
Weight Δ > 0.100 g (2× tolerance)	Significant: suspicious	Medium
Weight Δ ≥ +0.300 g (board-sized)	TAMPERED: DO NOT USE	High
CoM offset ≤ 0.7 mm	Centred	Medium
CoM offset 0.7–1.4 mm	Mild off-centre	Low
CoM offset > 1.4 mm	Significant off-centre	Medium
Heavy side follows the wallet after 180°	Mass is inside the device	Medium or higher

Confidence goes up when signals agree. If the weight is high and the CoM is off-centre, confidence is High. A normal weight plus a centred CoM is also High. Fewer than 3 weight readings lowers confidence one level. A board-sized overweight (≥ 0.3 g) is High on its own.

Reference weights and tolerances are examples, not Ledger specs. Calibrate with a known-genuine unit from the same batch, weighed on the same scale, and use its weight as your reference.

Until it's verified, keep the wallet in a Faraday bag (test the bag: call a phone inside it). Open source: github.com/lilaclilac09/tamper-check