Energy Converter - Online Joule Calorie BTU & kWh Tool
Convert energy units: Joule, calorie, BTU, kilowatt-hour, electronvolt. Useful for science and household energy calculations. Fully local.
UD5 Toolkit
Calculate the perfect wax to fragrance oil ratio for your handmade candles
Always use a digital scale for wax and fragrance oil. Volume measurements are inaccurate due to varying densities.
Add fragrance oil at 175–185°F (79–85°C) for soy wax. Too hot may burn off the scent; too cool won't bind properly.
Always test a small batch with new fragrance oils. Some scents may require different ratios for optimal hot throw.
Fragrance load (or fragrance oil ratio) is the percentage of fragrance oil relative to the weight of the wax. For example, an 8% fragrance load means you add 8 grams of fragrance oil for every 100 grams of wax. This is the standard way candle makers measure and communicate scent strength. The total blend weight would be 108g (100g wax + 8g FO).
Different waxes have different maximum fragrance load capacities—exceeding the recommended range can cause the fragrance oil to seep out (sweating), poor burn performance, or even fire hazards.
Soy wax typically holds 6% to 10% fragrance oil. For most soy waxes (like Golden Brands 464), 8% is the sweet spot—providing excellent hot throw without causing wicking issues or fragrance seepage. Some premium soy waxes can hold up to 10–12%, but always check your wax manufacturer's specifications.
Pro tip: If you're using essential oils instead of synthetic fragrance oils, start with a lower ratio (4–6%) as essential oils can be more volatile and may cause burning issues at higher concentrations.
To calculate for multiple candles:
Our calculator above automates all of this—simply enter your numbers and get instant results. You can also use the multi-container mode for different sized jars.
Poor hot throw can result from several factors:
Use our calculator to ensure you're using the right fragrance ratio, then experiment with cure times and wick sizes.
Yes, you can absolutely use too much fragrance oil! Exceeding your wax's maximum fragrance load can cause:
Always stay within your wax manufacturer's recommended fragrance load range. Our calculator's wax type selector shows the safe range for each wax.
These terms are often used interchangeably but can mean different things:
Our calculator uses the fragrance load method (FO relative to wax weight), which is the industry standard and what most candle supply manufacturers specify. For example, at 8% load with 200g wax, you get 16g FO and 216g total blend.
An 8 oz jar doesn't hold 8 oz of wax—containers are typically measured by water volume, and wax is less dense than water. As a rule of thumb:
The best approach is to fill one container with water, weigh the water (1g water ≈ 1ml), then multiply by 0.86 (the approximate density ratio of wax to water). Or simply test-fill one jar with wax and weigh it. Enter that measured weight into our calculator above.
Always measure by weight using a digital scale. Fragrance oils have different densities—1 fluid ounce of one oil might weigh 28g while another weighs 32g. Using volume (teaspoons, tablespoons, or fluid ounces) leads to inconsistent results.
A good digital scale accurate to 0.1g is an essential tool for candle making. Our calculator provides results in weight units (grams or ounces) for this reason. If you need volume estimates, check your specific fragrance oil's density/specific gravity from the supplier's SDS sheet.
We recommend adding 5–10% extra wax to account for:
Our calculator's waste compensation slider defaults to 5%. For very small batches (fewer than 4 candles), consider 10% since the relative loss is higher. For large production runs, 3–5% is usually sufficient.
Our candle making calculator uses the standard industry formula:
All calculations update in real-time as you adjust inputs. You can switch between grams and ounces, choose from common wax types with their recommended fragrance load ranges, and account for multiple container sizes. The results show exactly how much wax and fragrance oil to measure out for your project.
Convert energy units: Joule, calorie, BTU, kilowatt-hour, electronvolt. Useful for science and household energy calculations. Fully local.
Log your daily plastic use and see monthly weight estimate. Help track reduction goals. Data stays local. Motivate eco-friendly habits.
Estimate BAC based on gender, weight, drinks consumed, and time. Uses Widmark formula. Educational tool, never encourage drunk driving. Local only.
Estimate calories burned during common exercises using MET values. Input weight and duration. Compare activities. Educational, not medical advice.
A full‑screen drawing canvas supporting multiple touch points simultaneously. Different colors per finger. Works on mobile.
Calculate the exact number of days, weeks, months, and workdays between two dates. Visual calendar highlights. Perfect for projects.
Calculate the exact amount of wax and fragrance oil needed based on container volume and desired scent load. DIY candle crafting.
Choose your cup size and sweetness level, and get exact proportions for tea, milk, syrup, and tapioca pearls. Perfect homemade boba every time.
Enter temperature and wind speed (or humidity) to get the 'feels like' temperature. Safety guidelines included.
Calculate resistor values for transistor fixed bias or voltage divider configuration. Quick quiescent point analysis.
Combine multiple identical batteries in series and parallel and see the resulting voltage and total capacity. Electronics helper.
Track your subscriptions, calculate monthly and yearly totals, and find savings by pausing unused services. Local data.
Determine the minimum sample size needed for a survey or A/B test with a given confidence level and margin of error.
Compute confidence intervals for a population mean (known/unknown sigma) and proportion. All popular Z/T values. Local.
Easily compute posterior probabilities given prior, likelihood, and marginal likelihood. Visual diagram. All local.
Enter a number to find its golden ratio long and short segments. Use for pleasing design layouts. Instant.
Calculate new dimensions while preserving aspect ratio, or find the ratio from width and height. For video and images.
Find out how large you can print based on image resolution in pixels. Understand DPI and megapixels.
Learn about f‑stops and their effect on light and depth. Calculate equivalent exposure adjustments. Educational.
Find the CAGR of an investment given start and end values over a time period. Instant growth rate.
Calculate your running pace per mile/km, finish time for a race, and split times. Essential for runners.
Measure your waist‑to‑hip ratio and learn about associated health risks. WHR interpretation. Educational only.
Find what day of the week any past or future date falls on. Uses Zeller’s congruence. Fun historical reference tool.
Enter two sides of a right triangle and get the third. Also gives area and perimeter. Simple and visual.
Find the centroid (center of mass) of any convex polygon by entering vertex coordinates. Useful for physics and design.
Enter a chemical formula (e.g., H2O, C6H12O6) and calculate its molar mass. Handles parentheses and hydrates. Pure frontend.
Estimate monthly car loan payments with trade-in, down payment, and sales tax options. Amortization schedule included. Client-side calculation.
Project your retirement savings growth with monthly contributions, employer match, and CAGR. Interactive chart. Financial data stays on your device.
Estimate body fat percentage using the US Navy circumference method or BMI-based formula. Private and instant, all data stays on your device.
Calculate with binary numbers: addition, subtraction, multiplication, and division. Also bitwise AND, OR, XOR. Programmer's tool, fully client-side.