What is Candle Burn Rate?
Candle burn rate measures how much wax a candle consumes per hour of burning. This metric is essential for candle makers to determine burn time, optimize wick size, and ensure consistent performance. The burn rate is typically measured in ounces per hour (oz/hr) and helps in calculating how long a candle will last based on its weight.
Formula
The candle burn rate is calculated using this simple formula:
[
\text{CBR} = \frac{W}{T}
]
Where:
- CBR = Candle Burn Rate (oz/hr)
- W = Change in Weight (initial weight - final weight, in oz or g)
- T = Total Burn Time (hours)
How to Calculate Candle Burn Rate
- Weigh your candle before lighting it
- Burn the candle for a measured period (typically 3-4 hours)
- Extinguish and cool the candle completely
- Weigh the candle again after it has cooled
- Calculate the weight difference (initial weight - final weight)
- Divide the weight difference by the total burn time
Example Calculation
Let's say you're testing a new candle:
- Initial weight: 8 oz
- Weight after burning: 5 oz
- Burn time: 3 hours
Calculation:
[
\text{Change in Weight} = 8 \text{ oz} - 5 \text{ oz} = 3 \text{ oz}
]
[
\text{Burn Rate} = \frac{3 \text{ oz}}{3 \text{ hours}} = 1 \text{ oz/hr}
]
This means your candle burns at a rate of 1 ounce per hour.
Factors Affecting Burn Rate
- Wick size: Larger wicks create bigger flames and faster burn rates
- Wax type: Different waxes (soy, paraffin, beeswax) have different burn characteristics
- Container diameter: Wider candles typically burn faster than narrow ones
- Fragrance load: Higher fragrance oil content can affect burn rate
- Air circulation: Drafts can increase burn rate
- Burn pool depth: A deeper melt pool burns wax more efficiently
Ideal Burn Rates
- Pillar candles: 0.5-0.75 oz/hr
- Container candles: 0.75-1.0 oz/hr
- Votives: 0.25-0.5 oz/hr
- Tealights: 0.15-0.25 oz/hr
Why Burn Rate Matters
Understanding your candle's burn rate helps you:
- Predict burn time: Divide total candle weight by burn rate
- Optimize wick selection: Too fast means oversized wick; too slow means undersized
- Cost pricing accurately: Know how long products last
- Ensure safety: Prevent tunneling and excessive heat
- Maintain quality control: Consistent burn rates mean consistent products