ipad dosn't charge

As described, your iPad battery may be reaching the end of its usable working life - or is failing - which for older models of iPad is to be expected. All rechargeable batteries have a finite lifespan - after which their performance becomes insufficient for normal use.

An iPad battery is rated to retain 80% of its original capacity after 1000 full recharge cycles - a full cycle being any combination of charging that sums to 100% (e.g., 50 + 20 + 15 + 10 + 5 = 100 = 1 full charge cycle).

These support pages should help with troubleshooting battery and charging issues:

Charge and monitor the iPad battery - Apple Support

If your iPad won't charge – Apple Support

Troubleshooting generally requires substitution of the Power Adapter and cable for another known-good item. Most models of iPad require a Power Adapter rated at 12W or greater to reliably charge. 5W Power Adapters intended for older models of iPhone are inadequate to charge an iPad; if the iPad charges at all, charging will be very slow.

Be aware that many computer USB ports cannot source sufficient power to charge an iPad. Unless explicitly designed for charging connected devices, computer USB ports are typically limited to 0.5-1A @5V (i.e., 2.5-5.0W).

If you continue to experience difficulties when using an appropriate Power Adapter of 12W or greater, you might be best advised to seek assistance directly from from Apple Support - and request a remote diagnostic test. You can contact the Support Team using the Get Support link at top-right of this page. Alternatively, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/gb/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to test and assess your iPad, Power Adapter and cable(s):

Genius Bar Reservation and Apple Support Options - Apple

For eligible devices that remain in hardware support, battery service is available. Details can be found here:

iPad Service & Repair - Apple Support