Burning time of candles: how to determine it?

Weigh the candle at the start of burning and note the gross weight (including the container). Then let it burn for 4 hours. Weigh it at the end of the burning time. Write down the difference in weight and divide by 4. This will give you an approximate amount of wax burned per hour. 

To know the total burning time of the candle, you should find out the amount of wax in the container (net weight). If you have an empty container of the same size, weigh it and subtract this weight from the weight of the candle you have made. This gives you the net weight. Then divide this weight by the amount of wax you burned per hour. This will give you the total number of hours the candle will burn.

Ideally, you fill in the table when the candle has burned for 4 hours (this is the standard for burning tests) and continue to weigh the candle and note how much it burns until it is completely burnt. Then add up the hours burned. The candle will start to burn hotter (less efficiently) towards the end of the burn, so the actual hours may be less.

If it burns 3-4g per hour, you can say that the candle is burning efficiently, not too fast.