A faulty charger can disrupt your everyday use. Whether your laptop no longer charges properly or your old adapter is lost, it’s crucial to choose a new charger carefully to keep your device safe. Here’s a practical guide to help you make the right choice.
The technical information to gather before buying
What you absolutely need to know
Before ordering a charger, take the time to collect these key details:
- The exact model of your laptop
- The reference of the original charger (shown on the label)
- The voltage in volts (V)
- The current in amperes (A)
This information is usually written on the charger label or on the underside of the laptop, sometimes inside the battery compartment.
Some basic compatibility rules
- A maximum variation of 1 volt is generally acceptable.
- The new charger can supply more amperes than the original, but never less.
Making sure the connector is compatible
Taking the right measurements
To ensure perfect compatibility with your laptop, measure the diameter of the connector:
- Outer diameter (in mm)
- Inner diameter (in mm)
Use a fine ruler or a vernier calliper to get accurate measurements. The size is often written like this: outer-inner.
A concrete example
A connector marked 7.9-5.4 means:
- 7.9 mm outer diameter
- 5.4 mm inner diameter
Both of these values must match your device to ensure a stable connection.
Common examples of connectors used
Here is a simple overview of the most commonly used connectors by type:
| Manufacturer | Connector diameter (mm) |
| Type 1 | 5.5-2.5 / 4.8-1.7 / 7.4-5.0 |
| Type 2 | 5.5-2.5 / 5.5-1.7 |
| Type 3 | 5.5-2.5 / 7.4-5.0 |
| Type 4 | 5.5-2.5 / 6.3-3.0 |
| Type 5 | 5.5-2.5 / 7.9-5.4 |
| Type 6 | 6.5-4.4 |
| Type 7 | 5.5-2.5 / 6.5-4.4 |
| Type 8 | 5.5-3.0 |
This information is for guidance only. Always check the exact dimensions of the charger you are looking for.
Buying your charger safely: precautions to take
Where to buy and what to check?
You can buy your charger online or from a specialist shop. The main thing is to make sure it is a product that is:
- New (avoid heavily used second-hand items)
- Certified (with CE marking or equivalent)
- Guaranteed (a minimum of 6 months is recommended)
Checks before you order
Before completing your purchase:
- Confirm the compatibility of the voltage and current
- Check the exact type of connector
- Make sure the product meets safety standards
Conclusion: take your time to avoid mistakes
Buying a charger is not something to rush. A poor choice can damage your battery or stop it charging altogether. By following these simple criteria, you make a safe purchase and extend the life of your laptop.
A good charger is the foundation for working, gaming or browsing with peace of mind.
