Anti-Magnetic Watches: The Technology That Fights Invisible Forces
The Invisible Threat
Magnetism is everywhere — laptop speakers, phone cases, magnetic clasps, fridge doors. It is also the #1 cause of sudden accuracy problems in mechanical watches. Here is how anti-magnetic technology works.
How Magnetism Affects Watches
The hairspring — the delicate spiral spring controlling the balance wheel — is made of metal alloy. When magnetized, adjacent coils stick together, effectively shortening the spring. Result: the watch runs dramatically fast, sometimes gaining minutes per day.
Anti-Magnetic Solutions
- Soft iron inner case: a Faraday cage around the movement — blocks magnetic fields from reaching the hairspring. Used in IWC's Ingenieur and some Seiko models
- Non-magnetic hairspring: silicon or silicon-based alloys that are inherently non-magnetic. Increasingly common in modern movements
- Non-magnetic alloys: Parachrom (Rolex), Nivarox (industry standard) — reduced magnetic sensitivity
What "Anti-Magnetic" Ratings Mean
The ISO 764 standard defines anti-magnetic watch performance: the watch must maintain accuracy after exposure to a 60 gauss magnetic field. Some watches exceed this significantly — Omega's METAS-certified watches resist 15,000 gauss.
Practical Reality
Most daily magnetic exposure (phones, laptops, bags) is under 60 gauss — well within standard watch resistance. The problems come from concentrated sources: magnetic clasps, tablet cases, speaker magnets. Awareness prevents 90% of magnetization issues.
Frequently Asked Questions
Is my watch anti-magnetic?
Check the spec sheet. Most modern mechanical watches have basic resistance; "anti-magnetic" labeled watches have enhanced protection.
Can I demagnetize at home?
Yes — a demagnetizer tool costs a few dollars. See our magnetism guide.
Do our watches have anti-magnetic protection?
The NH35/NH34 family has standard magnetic resistance. Enhanced protection requires specialized movements.