How burn time is worked out
A container candle consumes somewhere between 6 and 9 grams of wax an hour. Divide the wax weight by each figure and you have the plausible range. That is the whole calculation, and it is why no honest version of this tool gives a single number.
What actually drives the number
Wax weight sets the ceiling. Everything else sets where in the range you land:
- Wick size — the dominant factor. Going up one size can cut total burn time substantially.
- Vessel diameter — a wide jar needs a bigger melt pool, which means a bigger wick and a faster burn.
- Fragrance load — more oil generally burns a little quicker.
- Draughts — a candle near a door or a vent flickers, burns unevenly and gets through wax faster.
- How the customer burns it — short burns cause tunnelling, which strands wax on the sides and never recovers it.
Labelling honestly
Quote the conservative end. If the range says 22 to 33 hours, put approximately 20 on the label. Nobody complains that a candle lasted longer than promised, and an overstated figure is the kind of thing that generates refund requests and poor reviews.
Before you print anything, do a real test burn. Light one from the actual batch, in a normal room, and time it across several sessions until it is done. That number beats any calculator, including this one.
Safety information customers need
Separate from burn time, most markets expect basic safety guidance on or with the candle: never leave a burning candle unattended, keep away from children, pets and anything flammable, burn on a heat resistant surface, trim the wick before each use, and stop burning when a small amount of wax remains at the bottom. Requirements for labelling, CLP classification and safety assessments differ by country — check what applies where you sell before going to market.