Candle Burn Time Calculator
Burn the candle once and weigh it before and after: that gives grams per hour. Dividing the wax by it gives the hours left. The wick size sets the rate, so the same wax in a thicker wick burns away faster.
Your numbers
Burn time
25.7h
Burn rate
7g/h
Formula
Burn time = Wax needed ÷ Burn rate
Keep single burns under about four hours. Longer than that overheats the wax and sooty carbon builds on the wick. The first burn is worth running until the whole surface has melted.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Wax needed (g)The wax to melt, by weight. | 180 | 1 and up |
| Burn rate (g/h)Wax lost per hour; the wick size sets it. | 7 | 0.5 and up |
Step by step
Quick reference table
Results when only Wax needed (g) changes and everything else stays put.
| Wax needed (g) | Burn time (h) | Burn rate (g/h) |
|---|---|---|
| 90 | 12.9 | 7 |
| 135 | 19.3 | 7 |
| 180 | 25.7 | 7 |
| 270 | 38.6 | 7 |
| 360 | 51.4 | 7 |
What each result means
| Result | At default values |
|---|---|
| Burn time (h)Hours until it is spent. | 25.7 |
| Burn rate (g/h)Wax lost per hour; the wick size sets it. | 7 |
Common mistakes
Keep single burns under about four hours. Longer than that overheats the wax and sooty carbon builds on the wick. The first burn is worth running until the whole surface has melted.
Glossary
- Wax needed
- The wax to melt, by weight.
- Burn rate
- Wax lost per hour; the wick size sets it.
- Burn time
- Hours until it is spent.
Frequently asked questions
Q. How is Candle Burn Time Calculator calculated?
Burn time = Wax needed ÷ Burn rate — Burn the candle once and weigh it before and after: that gives grams per hour. Dividing the wax by it gives the hours left. The wick size sets the rate, so the same wax in a thicker wick burns away faster.
Q. Can you walk through an example?
With Wax needed 180g, Burn rate 7g/h, the answer is Burn time 25.7h.
Q. What do I need to enter?
Enter Wax needed, Burn rate. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Wax needed (g) moves the answer to Wax needed (g) 90 → Burn time (h) 12.9 and Wax needed (g) 360 → Burn time (h) 51.4. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
Keep single burns under about four hours. Longer than that overheats the wax and sooty carbon builds on the wick. The first burn is worth running until the whole surface has melted.
Related calculators
Materials differ in density and absorption. If your label states a figure, use it — the defaults here are only common values.