Candle burn time explained: what 25 hours really means

Every candle lists a burn time. Ours says approximately 25 hours. But what is that number actually measuring, and why do two candles of the same size sometimes claim wildly different figures? Here is the plain version.

What burn time measures

Burn time is the total number of hours a candle will burn across all its sessions, from first light to the point the wax runs too low to burn safely, around 1cm from the base. It is not one continuous burn; no candle should be burned for a day straight. A 25-hour candle burned in sensible two-to-three-hour evenings is roughly ten evenings of use.

Why the same size can burn differently

Three things set burn time more than anything else:

The wax. Softer, lower-melt-point waxes like coconut wax burn at a lower temperature. The trade is usually a cleaner, more even, more fragrant burn rather than a marathon one. Harder paraffin can post longer numbers while burning hotter and sootier.

The wick. A thicker wick makes a bigger flame and eats wax faster. Wick choice is a balance: too small and the candle tunnels, too large and it races. Our cotton wicks are sized for an even melt pool on a 155g candle, not for the biggest number on a label.

Your habits. An untrimmed wick, a draughty windowsill, or hour-long micro-burns that never reach a full melt pool will all shorten a candle's useful life. The habits that protect burn time are in our Burn & Care guidance.

The arithmetic worth doing

Price per hour is a fairer comparison than price per candle. A Limewick Personal candle is £12 for approximately 25 hours, which is roughly 50p an hour of burn. A £4 supermarket candle that manages 15 hot, fast hours is not far off the same rate, with a different wax, a throwaway jar and a scent that usually fades sooner. Cheap and expensive candles are closer per hour than the shelf price suggests; the difference is what those hours are like.

Getting all 25 hours

Three habits cover most of it:

1. First burn to the edge. Let the melt pool reach the vessel wall on the first light, about two to three hours. This sets the burn pattern for the candle's whole life.
2. Trim to 5mm. Before every burn. A trimmed wick burns slower, cleaner and lower.
3. Two to four hour sessions. Long enough for a full pool, short enough to keep the wick tidy. Then stop burning at the last centimetre; that wax is the candle's foundation, not its finale.

One number, honestly stated

Burn times are approximations by nature; your room, your habits and even the season change the result. We state approximately 25 hours for the 155g candle because that is what our burns show with the habits above. If a candle the same size promises 60, ask what kind of hours they mean.

Ten calm evenings, roughly 50p each: Greenhouse Retreat is a good first ten. The rest of the range is here.