Max charger power for 2026 iPad Air 13'' M4?

While your iPad will charge using a USB power supply rated at 12W (i.e. 2.4A @5V) or greater, the iPad will charge at its maximum charging rate when connected to a 30W USB-C Power Adapter that supports USB PD (Power Delivery). While you can use a higher rated USB-C power source, there is no benefit - as the iPad will only draw the power that it needs.

Some third-party USB-C power adapters (and portable PowerBanks) may not support USB PD. Power Delivery mutually negotiates the charging voltage; the source, load and cable are all elements involved in the negotiation protocol. Unless the Power Adapter explicitly supports USB PD, it will almost certainly fail to charge the iPad; proprietary charging standards, such as QC (Quick Charge), are not supported.

The iPad (and most well-designed devices) set the current they draw, not the charger, so it doesn't matter what charger you use as long as it's a decent one and not some cheap rubbish.