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How to Calculate Candle Burn Time
Burn time is measured, not guessed. Fix wick, wax, vessel and room conditions, then weigh consumption over timed burns.
When customers ask “how many hours?”, the label should rest on data. At Rufus Concept we estimate burn time from wax consumption rate, wick and vessel geometry. The method below works for home makers and small ateliers.
How Long Should A Session Last?
There is no universal hour count. Container candles should run long enough for a full melt pool to the edges; endless burns overheat glass. Pillars depend on wick and diameter balance. Test before you print claims.
- First light: until a full melt pool forms
- Later burns: similar length, wick trimmed each time
- Never leave a candle unattended—testing does not change that rule
Variables That Move The Clock
- Wick type and length: Cotton and wood wicks consume at different rates.
- Wax formula: Soy, paraffin, beeswax and additives change melt energy.
- Fragrance load: Higher loads can alter flow and flame.
- Vessel diameter and fill weight: Wider pools usually burn faster.
- Room: Drafts, temperature, humidity.
Simple Weighing Test
- Record starting weight in grams.
- Trim wick to about 5–7 mm; light in still air.
- Extinguish after a set time (e.g. 2 hours) and cool.
- Weigh again; difference = wax used.
- Usable remaining wax ÷ hourly use ≈ hours left.
| Measure | Example |
|---|---|
| Start | 220 g |
| After 2 hours | 196 g |
| Use rate | 12 g/hour |
| Usable left (e.g. 180 g) | ~15 hours |
Exclude the unsafe heel that will not burn cleanly. Keep separate rows for each fragrance SKU.
Control The Room
Do not test under an air vent. Same table, same trimmer, same duration. Average at least three repeats before labelling.
For Longer, Even Burns
- Trim before every lighting.
- Complete the first melt pool to stop tunneling.
- Freeze the formula: wax, fragrance, dye, pour temp.
- Lock vessel choice to wick tests.
- If you use stearic acid, dose it and write it down.
Burn time is a weigh-book result, not a slogan. Measure, average, label conservatively. Repeating the same test with Rufus Concept materials keeps hour ranges honest in your workshop.
Labels And Customer Copy
If your average is 28 hours, print “about 25–30 hours.” A single number disappoints outside the lab. Add first-burn and wick-trim notes to the care card.
- Average three repeats per SKU.
- Note summer/winter room differences.
- Retest when the vessel changes—wider jars usually burn faster.
Wholesale buyers trust a short PDF: wax code, wick, g/hour average and suggested session length. Records built on Rufus Concept materials keep that language consistent beyond Bursa.
FAQ
Do wood wicks differ from cotton?
Often yes. Run a separate weigh series for wood wicks.
Same math for gel?
Gel density and burn differ—remeasure; do not copy the paraffin table.
Always log date, room temperature and wick code. The same formula may burn slower in winter and faster in summer. A range on the label absorbs that drift. For wholesale, share test conditions briefly—it builds trust.