Panasonic  (1)

model device
The laptop model is usually located on the bottom of the device. Read it and enter it into the shop's search engine.
e.g. Asus K53SV / HP Pavilion G6 / MacBook Pro 13 A1278

value of INPUT / OUTPUT
On the nameplate of the power supply, the voltage and current values are marked as OUTPUT, and on the bottom of the laptop the same parameters are marked as INPUT. Read some of them and enter them into the store's search engine, adding the brand of the device to them. Make sure the plug of the found power adapter is correct.
e.g. Asus 19V 4.74A / Dell 19.5V 4.62A / Lenovo 20V 3.25A.

With such small differences, it is acceptable. However, we must remember to use power supplies with higher power, not less, because at lower power the laptop may not work.

It will be suitable for our laptop if the connector diameter meets the outer diameter specification, eg 5.5mm, and the output parameters are compatible. What are output parameters? It is the value of voltage[V] and current[A] given by the power supply for a laptop, eg 19V 4.74A.

When choosing a new power supply for your laptop, you should check the voltage of the charger - this parameter should match your original device.