The length of the candle depends on the composition of the wick and the hardness of the wax. But if he got the candles from IKEA, a Swedish company; in all likelihood we have the same ones. Probably all made in China, though.
Be very careful that the wick doesn’t contain a metal thread. I was given one and didn’t realize it. It left black soot all over everything in the house. It was invisible at the time. Imagine what we were breathing.