Charging ipad overseas

all Apple USB Power Adapters are designed for use with AC-power sources rated to provide 100VAC to 240VAC at 50Hz to 60Hz. Apple iPad USB power adapters also comply with the IEC/UL 60950-1 and IEC/UL 62368-1 standards for use with power sources rated to provide 115VAC at 400Hz (typically found onboard commercial airlines).

While all Apple-manufactured Power Adapters will be fully usable when travelling internationally, you may require a simple pin-adapter to allow the Power Adapter to be used with AC power outlets in different countries. For example, a US flat 2-pin connector will require an adapter for the standard European round 2-pin socket, or UK square 3-pin. Travel adapters are readily available.

The iPad, no. It expects 5v DC only.

The charger brick is the one that needs to support multiple voltages and all Apple charges do so. You should just need a plug adapter to connect it to the wall.

Link->About Apple USB power adapters - Apple Support

If using a 3rd party charger, verify the technical specs on it and make sure it supports the voltages in the country you are going to.