Buying a replacement laptop charger can seem simple, but it is important to choose the right one. The wrong charger may not work properly, may charge slowly, or could potentially cause problems with your laptop.
This guide explains what to check before buying a laptop charger, including voltage, amps, wattage, connector size and compatibility.
1. Check the laptop make and model
The first thing to check is the exact make and model of your laptop. This is usually found on a label on the bottom of the laptop, inside the battery area on some older models, or in Windows system information.
For example, instead of only searching for “HP charger” or “Dell charger”, try to find the full model number of the laptop. This helps reduce the chance of ordering the wrong charger.
- Brand: HP, Dell, Lenovo, Acer, ASUS, Toshiba, Samsung and others.
- Model number: Usually printed on the base of the laptop or shown in system information.
- Part number: Some laptops have a specific product or service tag that can help identify the correct charger.
2. Check the voltage
Voltage is one of the most important things to check. It is usually shown on the original charger label as Output.
For example, a charger may say:
- Output: 19V
- Output: 19.5V
- Output: 20V
The replacement charger should match the required voltage for your laptop. Using the wrong voltage can stop the laptop charging correctly and may risk causing damage.
3. Check the amps and wattage
The charger label will usually show amps, often written as A. It may also show wattage, written as W.
For example:
- 19V 3.42A is roughly a 65W charger.
- 19.5V 4.62A is roughly a 90W charger.
- 20V 2.25A is roughly a 45W charger.
The wattage should be the same as, or higher than, the laptop requires. A charger with too low wattage may charge slowly, may get hot, or may not power the laptop properly when it is under load.
4. Check the connector tip size
Laptop chargers can look similar but have different connector tips. The connector is the part that plugs into the laptop.
Some common connector types include:
- Round barrel connectors
- Small pin-style connectors
- USB-C chargers
- Brand-specific charger tips
Even if the voltage and wattage are correct, the charger will not work if the connector is the wrong size or shape. Always compare the connector carefully with your original charger or laptop charging port.
5. Check if your laptop uses USB-C charging
Some modern laptops charge using USB-C, but not every USB-C charger is suitable for every laptop.
If your laptop uses USB-C charging, check the wattage required. Smaller laptops may use 45W or 65W, while larger laptops may need 90W, 100W or more.
You should also check that the charger supports the correct USB-C power delivery standard. A basic phone charger with USB-C is usually not suitable for charging a laptop.
6. Check the original charger label if you still have it
If you still have the original charger, the label is one of the best places to check the required specification. Look for the Output section.
You may see something like:
- Output: 19V 3.42A
- Output: 19.5V 4.62A
- Output: 20V 3.25A
You can use this information to compare against the replacement charger before buying.
7. Avoid very cheap or poor-quality chargers
Very cheap laptop chargers can be tempting, but they may not always be reliable. Poor-quality chargers may overheat, fail quickly, or deliver unstable power.
For regular use, it is usually better to choose a suitable replacement charger from a trusted supplier. This is especially important if the laptop is used for work, business or daily use.
8. Check whether the issue is actually the charger
Before buying a new charger, it is worth checking whether the charger is definitely the problem. Charging issues can also be caused by the laptop charging port, battery, motherboard, cable damage or software/power settings.
Signs the charger may be faulty include:
- No power light on the charger, if it has one
- The laptop only charges when the cable is held at an angle
- The charger gets unusually hot
- The cable is visibly damaged
- The laptop works with another compatible charger
If the laptop still does not charge with a known working charger, the issue may be with the laptop rather than the charger.
9. What information should you check before ordering?
Before ordering a replacement laptop charger, try to confirm:
- The laptop make and model
- The voltage required
- The amps or wattage required
- The connector tip size or USB-C requirement
- Whether the laptop needs an original, compatible or high-wattage charger
Need help choosing a laptop charger?
If you are unsure which charger is right for your laptop, IT Done Right can help point you in the right direction. A photo of your laptop model label, the original charger label, and the charging port can usually help identify the correct type.
You can browse laptop chargers in the IT Done Right Shop here: Shop laptop chargers .
If your laptop still does not charge after trying a suitable charger, you may need a repair instead. You can view our Laptop Repair Services page for help with charging ports, batteries, power issues and other laptop faults.
Need advice before ordering? Contact IT Done Right and we will be happy to help.