Watch Magnetism: Signs Your Watch Is Magnetized, How to Test It

If your automatic watch suddenly starts running much faster than usual, magnetism is one of the most common causes. Modern life is full of magnets—phone cases, laptop speakers, handbag clasps, and chargers—so this issue is more normal than most owners think.

If you’re new to automatic watches, start here: What Is an Automatic Watch? Pros, Cons & Who Should Buy One

Quick Answer: What Magnetism Does to a Watch

A magnetized watch often runs fast because magnetic fields can cause the hairspring (or other components) to behave abnormally—effectively changing the oscillation rate.

If you’re trying to understand what “normal” accuracy looks like first, read: Are Automatic Watches Accurate?

7 Common Signs Your Watch Is Magnetized

Sudden gain in time (e.g., +30 to +120 seconds/day overnight)
Accuracy becomes erratic (fast one day, very fast the next)
The watch used to be stable and suddenly isn’t
Time drift appears after travel or new daily routines (new laptop stand, new phone case, new bag clasp)
The watch starts running fast shortly after being placed near electronics
You hear/feel nothing wrong mechanically, but accuracy is clearly off
Multiple mechanical watches in the same place start behaving oddly

Where Magnetism Usually Comes From (Real-Life Sources)

Phone/tablet magnetic cases and covers
Laptop speakers, desktop speakers, soundbars
Magnetic clasps in bags/bracelets
Wireless chargers and some charging stands
Toolboxes, magnetic trays, fridge magnets
Some induction cooktops and appliances (don’t rest a watch nearby)

Simple At-Home Tests (No Special Tools)

Test #1: The “baseline check”

If you know your watch’s normal rate (e.g., +6 s/day) and it suddenly jumps massively (e.g., +60 s/day), magnetism is a strong suspect.

Test #2: Compare positions for one night

Put the watch in a consistent resting position overnight (dial up). If the drift remains unusually large and fast, magnetism may be involved.

Note: These tests don’t prove magnetism, but they help you decide whether it’s worth demagnetizing.

If you want the mechanical basics behind why accuracy changes, read:
How Does an Automatic Watch Work? Simple Beginner Guide

How to Fix a Magnetized Watch (Safest Options)

Option A (Best): Ask a watchmaker to demagnetize

Most shops can test and demagnetize quickly. This is the safest route.

Option B: Use a quality demagnetizer (only if you’re careful)

Demagnetizers are common tools, but technique matters. If you’re not confident, use Option A.

Important: If your watch also shows signs like fog under the crystal, rough crown feel, or power reserve drops, don’t assume magnetism is the only issue—service may be needed.

Service guide: How Often Should You Service an Automatic Watch?

Care routine:
How to Maintain an Automatic Watch: Daily Wear, Storage & Servicing

How to Prevent Magnetism (Practical Habits)

Don’t rest your watch on phone cases, speakers, or magnetic clasps
Keep it away from charging stands/pads
Store watches in a consistent place away from magnetic objects
If you rotate watches, consider a storage location that’s “electronics-free”

If you store your watch often and it stops off-wrist, that’s usually normal power reserve, not magnetism:
Do Automatic Watches Stop If Not Worn? Power Reserve, Why It Happens & Easy Fixes

Magnetism vs “Needs Service”: How to Tell the Difference

Symptom	More Likely Magnetism	More Likely Service Needed
Sudden large gain (fast)	✅ Yes	Sometimes
Gradual worsening over years	Less likely	✅ Yes
Power reserve suddenly drops	Not typical	✅ Yes
Rough crown / moisture	No	✅ Yes
After demagnetizing, accuracy returns	✅ Yes	Not necessarily

FAQ: Watch Magnetism

Can magnetism permanently damage my watch?

Usually not. Magnetism often causes abnormal timekeeping and can be corrected by demagnetizing.

Why does magnetism usually make a watch run fast?

It can cause parts (especially the hairspring) to behave as if the effective spring length/tension changes, increasing rate.

How often does magnetism happen?

More than most people think—modern daily environments contain many small magnets.

Should I stop wearing the watch if it’s magnetized?

You can, but it’s better to fix it soon so you’re not tracking incorrect time.

If my watch runs fast, is it always magnetism?

No. Regulation, shocks, or aging lubrication can also cause drift. Start with the accuracy guide:
Are Automatic Watches Accurate? Real-World Tolerances, Why They Drift & How to Improve Accuracy