Does iPad 9th Gen support fast charging?

All Lightning cables built to Apple’s MFi certification standards are capable of supporting Apple’s maximum input current. I believe for USB-A that’s 2.4A. With USB-C that’s a bit trickier because of support for different voltages, but 20W was noted for the boxed power adapter (5 or 9V).

As long as it’s MFi (the “Made for iPhone/iPad” description) and licensed by Apple, you should be capable of supporting the maximum input power. It wouldn’t have to be Apple OEM.

No. None of those 3 devices support Fast Charging. For fast charging you need an iPhone 8 or later and iPads with USB-C ports instead of lightning.

With that said, using a 20 watt charger will make them charge a bit faster than using say a 12 watt charger but it's not considered actual Fast Charging.

Also, the cable used is not as important as the power adapter. You won't get fast charging with a new cable unless you have a power adapter with enough wattage for it.

Any certified Lightning to USB-C cable should work for the faster charging with a decent enough power adapter.

NDakotaGirl wrote:

I just purchased a new 9th Gen iPad. I also have an old iPad Air 2 and a iPhone 7. I need to buy a new cable and need to know if any of these support fast charging.

Short answer:

The charging cable is not relevant to the charging speed. The same USB-C to Lightning cable works for all three.

The same Apple 20W charger will work for all three, too.

Long answer:

The voltage and the wattage available from the charger is relevant to fast charging, but a charger such as the Apple 20W can also supply the lower voltage and the wattages required for older devices.

Yellow is the older 5V charging and can supply 5W, 10W, and 12W, while red is the newer 9V 20W “fast” charging:

There are cases where a charger cannot supply the required voltage, or cannot supply enough wattage. (The Apple 29W is pretty limited here, for instance.) This will mean charging is slow or is unavailable, but the connection won’t physically damage the connected device.

Above is with a certified charger. There’s unfortunately been lots of cheap, sketchy, or uncertified junk around.

Apple charger info: About Apple USB power adapters - Apple Support

Also:

Everything you wanted to know about charg… - Apple Community

Apple USB-C power adapter volts, amps - Apple Community

Your iPad9 will likely have been supplied with a 20W USB-C Power Adapter - along with a 1m USB-C to Lightning cable. The 20W Power Adapter will charge your iPad9 at its maximum supported charging rate.

You can also use the Power Adapter with both your iPhone7 and iPad Air2 - both of which have Lightning connectors.