how long does a soy candle last?

A 170ml soy candle gives you about 35 hours. A 500ml gives about 80. Those are the honest numbers, and what you actually get depends on four things you control.

What that means in weeks

Nobody burns a candle for 35 hours straight. In practice:

• Two hours, three evenings a week — about six weeks
• Three hours, most evenings — about two and a half weeks
• Weekends only — three months or so

Which is worth knowing before you buy. A candle you light every night isn't a two-month purchase.

1. The first burn

Soy wax remembers. The first time you light it, let the melted pool reach the edge of the glass — two to three hours in a normal jar. If you don't, it will tunnel down the middle for the rest of its life and you'll lose a third of the wax to the walls.

2. Trimming the wick

5mm, before every single burn. Nail scissors are fine. An untrimmed wick burns hotter, eats wax faster, smokes, and leaves black marks up the glass. This is the single easiest thing to do and the one everyone skips.

3. How long you burn it

Between two and four hours. Under two and the pool doesn't reach the edge. Over four and the jar overheats, the wick mushrooms, and you get soot instead of scent. Blow it out, let it set, light it again later.

4. Where it sits

Away from draughts, radiators and open windows. A flame being pushed sideways burns unevenly and faster. Direct sunlight also fades the scent in the unburnt wax, so a windowsill is the worst place for a candle even when it's not lit.

Why soy rather than paraffin

Soy burns cooler and slower, so you get more hours from the same jar. It's also a plant wax rather than a petroleum by-product, and it washes out of the glass with hot soapy water — which paraffin does not.

The trade-off is honest: soy doesn't throw scent quite as hard as paraffin, and it can look frosty or uneven on top. That's the wax crystallising, it's normal, and it doesn't affect the burn.

When to stop

Stop when there's about 1cm of wax left. Below that the jar gets hot enough to be a problem. Then wash it out and keep it — mine are amber glass with a black lid and they're worth having for pens and hairgrips.