So you’ve crafted your candles, you’ve perfected your packaging and now you’re ready to sell, but you want to tell your customers exactly how much burn time they will get out of their candle. Here we will show you to calculate it.
It’s important to note that not every candle is the same. Depending on which wax, container, fragrance, colours and wick you use will impact a candle’s burn time. So, the same burn time won’t always be applicable to every candle in your collection. We’ve put together our guide for working out the burn time for your candle below!
How To Work Out Your Burn Time
- Start by weighing your finished, unburned candle on your scales (gross weight). If it is a container candle, you will need to subtract the weight of the container when empty. This is the original weight of the candle alone (net weight).
- Next, you’ll want to go ahead and light your candle and allow it to burn for the usual four hours. For tips on how to burn a candle safely and correctly you can read our guide here.
- After your initial four hours, extinguish the candle and allow it to cool and let the wax set fully. You’ll want to go ahead and weigh your candle again, remembering to subtract the weight of the container again, you may want to keep a note of your candle container weights when empty. This is your post-burn weight.
- You’ll then want to subtract your post-burn weight from the original weight of your unburned candle at the start, then divide this by the number of hours you burned your candle. The number you get is the hourly burn rate.
- To find the approximate burn time you need to divide the original candle weight (minus the weight of the container) by the hourly burn rate. This will tell you approximately how many hours your candle will burn for.
In Summary
To find the total number of hours the candle will burn, divide the original weight of the candle by the hourly burn rate.
Amount Consumed (Original weight – post-burn weight) ÷ Hours Burnt = Hourly Burn Rate
Original Weight (minus weight of container) ÷ Hourly Burn Rate = Approximate Burn Time
For Example
If my finished candle weighs 250g and my container weight 50g, then my original candle weight is 200g.
After 4 hours of burning my candle weighs 234g. I now take away the weight of my container (50g), meaning my candle now weights 184g. This is my post burn weight.
I now take away 184g from 200g, meaning that my candle burned away 16g in 4 hours. 16g divided by 4 hours is 4g per hour. This is my hourly burn rate.
I divide the original candle weight of 200g by the hourly burn rate of 4g per hour, and this gives me an approximate burn time of 50 hours.
Top Tips
Ensure you stick to the same unit of measurements for all of your weights, we suggest grams as this is what most people tend to work in, from weighing wax and fragrance to working out burn rate, be consistent in how you measure.
Grams are a smaller unit of measurement, which means you will end up with numbers that are easier to work with. For example: 5 grams/hour versus 0.16 ounces/hour.
It’s best to burn and measure your candle multiple times, your first test burn can sometimes be a little off as it is the first one, repeat testing will give you a more accurate representation of your candles burn time.
You must make sure that the wick you are using in your candle is the appropriate size. As you know, an over-wicked candle will burn more quickly, while an under-wicked candle will burn more slowly, ensure you select the right wick for an accurate burn time calculation.
If you have never conducted a test burn, you can read our blog; How To Take Test Burn Notes here, it’s important that your candle burns well without tunneling or sooting etc. before you spend time working out your candle’s burn time.