Is my Iphone 5 4g compatible

Depends on who your carrier is, whether or not you're in the home country of the iPhone, and the definition of 4G...
How to determine all of the above.

4G- HSPA+ data communications, released a few years after 3G, didn't get much traction as LTE exploded onto the scene in 2012.

LTE otherwise known as 4G LTE (a terribly named term imo)

America- Verizon/Sprint do not have the 4G H+ network, but they do have LTE.
T-mobile/At&t, yes they have both 4G and LTE.

Almost everywhere else on the planet (Excluding N. Korea, North/South pole, etc.) has 4G and LTE due to the popularity of the GSM standard.

Don't post rubbish ,of course the iPhone 5 is 4G capable

The iPhone 5 only ever worked with EE in the UK no other providers and no providers in Ireland

The 5S and the 5C work with 3, Meteor,and Vodafone in Ireland and any follow on products will be at least similar

According to GiffGaff, only EE support 4G LTE on the iPhone 5 in the UK. They sent me a refund for my 4G 'GoodyBag', and I had to go for a 3G 'GoodyBag' instead.

I'm having to buy a later iPhone now so that I can utilise 4G capability.

If anyone else in UK is using 4G LTE capability on their iPhone 5 (model A1429) on any other network than EE, please let us know... it will save me buying a new phone!

No because this is a user to user community wiith no Apple participation

see this to work it out

http://www.apple.com/iphone/LTE/

I phone 5 is not 4G enabled device.