How to Calculate Fragrance Load for Candles: The Complete Guide
Master fragrance load calculations for perfect candle scent throw. Learn the exact formulas, percentages by wax type, and avoid common mistakes that ruin scent performance.
Last updated: December 2025
Fragrance load is the single biggest factor in how your candles smell. Get it wrong and you'll have candles that barely throw scent—or worse, ones that sweat, tunnel, and won't stay lit.
This guide shows you exactly how to calculate fragrance load, what percentages work for different wax types, and the mistakes that ruin otherwise perfect candles.
In this guide:
- What fragrance load means and why it matters
- Fragrance percentages by wax type (soy, paraffin, coconut, beeswax)
- Step-by-step calculation formula with examples
- Batch calculations for production scaling
- Troubleshooting weak scent throw and common mistakes
What Is Fragrance Load?
Fragrance load is the percentage of fragrance oil in your total candle weight. It's calculated as:
Fragrance Load % = (Fragrance Oil Weight ÷ Total Candle Weight) × 100
Or working backwards (more useful):
Fragrance Oil Needed = Wax Weight × Fragrance Percentage
Example:
- You're making a 10 oz candle
- You want an 8% fragrance load
- 10 oz × 0.08 = 0.8 oz fragrance oil
Simple. But the percentage you choose matters a lot.
Fragrance Load by Wax Type
Every wax has a maximum fragrance capacity—the point where it can't absorb any more oil. Exceed this and the fragrance "sweats" out of the candle.
| Wax Type | Recommended Load | Maximum Capacity | Notes |
|---|---|---|---|
| Soy wax (container) | 6-8% | 10% | Wicking issues common above 7% |
| Paraffin | 6-9% | 10-12% | Blends with Vybar hold more |
| Coconut wax | 8-10% | 12% | Excellent scent throw |
| Coconut-soy blend | 7-9% | 10-12% | Popular for luxury candles |
| Beeswax | 4-6% | 8% | Natural honey scent competes |
| Palm wax | 6% | 6-7% | Lower capacity than other waxes |
| Parasoy blends | 6-9% | 10-12% | Check manufacturer specs |
Important: These are guidelines based on industry standards. Every specific wax brand has its own recommendations—always check your supplier's technical data sheet for exact limits.
The Fragrance Load Formula (Step-by-Step)
Step 1: Decide Your Target Percentage
For most container candles, start with 6-8%. The industry standard baseline is 1 oz fragrance per 1 lb wax (6.25%), which provides reliable scent throw without risking sweating or burning issues.
Quick rule of thumb: Start at 6% and increase by 0.5-1% increments if you need stronger throw.
Step 2: Weigh Your Wax
Always work in weight, not volume. A "10 oz candle" typically means the jar holds 10 oz—the wax weight varies by type.
Example container fills:
| Jar Size | Approximate Wax Needed |
|---|---|
| 8 oz jar | 5-6 oz wax |
| 10 oz jar | 6-7 oz wax |
| 12 oz jar | 7-8 oz wax |
| 16 oz jar | 10-12 oz wax |
Step 3: Calculate Fragrance Oil
Wax Weight × Fragrance Percentage = Fragrance Oil
Examples at 8% fragrance load:
| Wax Weight | Calculation | Fragrance Oil |
|---|---|---|
| 5 oz | 5 × 0.08 | 0.4 oz |
| 8 oz | 8 × 0.08 | 0.64 oz |
| 10 oz | 10 × 0.08 | 0.8 oz |
| 1 lb (16 oz) | 16 × 0.08 | 1.28 oz |
| 5 lbs (80 oz) | 80 × 0.08 | 6.4 oz |
Step 4: Add at the Right Temperature
Most fragrance oils should be added when wax reaches 185°F (85°C). This is the optimal temperature for fragrance and wax to bind together, confirmed by industry testing.
| Temperature | Result |
|---|---|
| Below 175°F | Fragrance won't bind properly; may pool or leach |
| 180-185°F | Optimal binding and scent throw |
| Above 200°F | Some fragrance volatiles may evaporate |
Pro tip: Stir for 2 full minutes after adding fragrance—short stirring prevents proper binding and causes weak scent throw.
Check your specific wax supplier's data sheet for any variations from this standard.
Batch Calculations (Scaling Up)
When you're making multiple candles, calculate fragrance for the entire batch:
Example: Making 24 candles
- Each candle uses 8 oz wax
- Total wax: 24 × 8 oz = 192 oz (12 lbs)
- Fragrance at 8%: 192 × 0.08 = 15.36 oz fragrance oil
Quick Reference Chart (8% Load)
| Batch Size | Wax per Candle | Total Wax | Fragrance Oil |
|---|---|---|---|
| 12 candles | 8 oz | 96 oz (6 lbs) | 7.68 oz |
| 24 candles | 8 oz | 192 oz (12 lbs) | 15.36 oz |
| 48 candles | 8 oz | 384 oz (24 lbs) | 30.72 oz |
| 100 candles | 8 oz | 800 oz (50 lbs) | 64 oz (4 lbs) |
What Happens When You Get It Wrong
Too Much Fragrance (Over-Loading)
Signs:
- Oily residue on candle surface (sweating)
- Fragrance pooling at the bottom
- Wick drowning in oil
- Poor or inconsistent burn
- Tunneling
- Smoking or sooting
Why it happens: The wax can't hold more oil than its capacity. The excess has nowhere to go.
Too Little Fragrance (Under-Loading)
Signs:
- Weak cold throw (can't smell it unlit)
- No hot throw (can't smell it burning)
- Customers complaining about lack of scent
Why it happens: Not enough fragrance molecules to disperse into the air when heated.
Fragrance Load vs. IFRA Limits
IFRA compliance sets maximum safe levels for individual fragrance ingredients. For candles (Category 12), most fragrance oils show 100% on IFRA certificates—meaning IFRA isn't the limiting factor.
For candles, your wax capacity is almost always the limiting factor, not IFRA.
This is because candles don't contact skin during normal use. The fragrance disperses into the air rather than being absorbed.
However, if you also make:
- Reed diffusers (Category 10A): IFRA limits of 5-25% become relevant. See our reed diffuser IFRA guide.
- Soap (Category 9): IFRA limits of 2-35% may restrict you. See our IFRA guide for soap makers.
- Lotions (Category 5): Much stricter limits apply
Always check IFRA certificates for products with skin contact. Even if your wax can hold 10%, if the IFRA certificate for that specific fragrance shows a lower limit for your product category, you must use the lower percentage.
Testing Your Fragrance Load
The "right" percentage depends on:
- Your specific wax brand
- The fragrance oil (some are stronger than others)
- Your jar size and wick
- Customer expectations
How to Test
Make 3 test candles with the same fragrance at different loads:
- 6%
- 8%
- 10%
Label each clearly with the percentage
Cure for 1-2 weeks (soy wax needs time)
Evaluate cold throw: Can you smell it at arm's length?
Burn test each: Does the scent fill a room?
Check for issues: Sweating, tunneling, sooting?
Pick the lowest percentage that gives good throw without problems
Why "Lowest Effective" Matters
- Less fragrance oil = lower cost per candle
- Less fragrance = fewer potential burn issues
- More isn't always better for scent throw
Some fragrances throw beautifully at 6%. Others need 10% to perform. Test each one.
Common Fragrance Load Mistakes
Mistake 1: Using Volume Instead of Weight
Fragrance oil is denser than wax. If you measure by volume (cups, tablespoons), you'll be inconsistent.
Always weigh your fragrance on a scale.
Mistake 2: Not Accounting for Wax Type
8% in paraffin behaves differently than 8% in soy. Know your wax's capacity.
Mistake 3: Assuming All Fragrances Are Equal
A "strong" fragrance like cinnamon might throw well at 6%. A delicate floral might need 10%. Test each fragrance individually.
Mistake 4: Changing Load to "Fix" Throw Problems
Weak scent throw isn't always a fragrance load problem. It could be:
- Wrong wick size
- Not enough cure time
- Poor quality fragrance oil
- Adding fragrance at wrong temperature
Don't just increase fragrance—diagnose the real issue.
Mistake 5: Ignoring Cure Time
Soy candles need 1-2 weeks to cure before evaluating scent throw. Testing fresh pours gives inaccurate results.
During curing, fragrance molecules bind more deeply with the wax. A candle burned at 3 days will have noticeably weaker hot throw than the same candle burned at 14 days.
Minimum cure times by wax type:
- Soy wax: 7-14 days (2 weeks ideal)
- Paraffin: 3-5 days
- Coconut/coconut blends: 7-14 days
- Palm wax: 5-7 days
Troubleshooting Weak Scent Throw
Weak scent throw is the #1 complaint from candle makers. Before increasing fragrance load, check these common causes:
Checklist: Diagnosing Weak Scent
| Issue | Symptom | Solution |
|---|---|---|
| Wrong wick size | Small melt pool, low flame | Wick up 1-2 sizes |
| Fragrance added too cool | Oily spots, pooling | Add at 185°F, stir 2 minutes |
| Not enough cure time | Fresh pour smells weak | Wait 7-14 days for soy |
| Low-quality fragrance oil | Good load, still weak | Test different suppliers |
| Olfactory fatigue | YOU can't smell it | Leave room 10 min, return |
| Fragrance load too low | Everything else checks out | Increase by 1% increments |
Important: Adding more fragrance won't fix wick, temperature, or cure time problems. It will just create new issues (sweating, tunneling, smoking).
The Olfactory Fatigue Trap
If you're testing candles all day, your nose "shuts off" to familiar scents. This is olfactory fatigue—not weak scent throw.
Test properly:
- Light the candle in a room you haven't been in
- Leave for 30-60 minutes
- Walk in and evaluate immediately
- Ask someone who hasn't been around your candles
Many "weak HT" problems are actually testing environment problems.
Quick Reference: Fragrance Load Calculator
Formula:
Fragrance Oil (oz) = Wax Weight (oz) × (Percentage ÷ 100)
Common Calculations:
| Wax Weight | 6% | 8% | 10% |
|---|---|---|---|
| 4 oz | 0.24 oz | 0.32 oz | 0.40 oz |
| 6 oz | 0.36 oz | 0.48 oz | 0.60 oz |
| 8 oz | 0.48 oz | 0.64 oz | 0.80 oz |
| 10 oz | 0.60 oz | 0.80 oz | 1.00 oz |
| 16 oz (1 lb) | 0.96 oz | 1.28 oz | 1.60 oz |
| 80 oz (5 lbs) | 4.80 oz | 6.40 oz | 8.00 oz |
Grams conversion: Multiply oz by 28.35 (e.g., 0.64 oz = 18.1g)
Stop Calculating Manually
When you're managing dozens of recipes with different fragrances, wax types, and batch sizes, manual calculations get messy fast. One decimal error compounds across an entire batch.
PetalMade automatically:
- Calculates fragrance load for every recipe
- Warns you before you exceed wax capacity
- Tracks IFRA compliance across all your products
- Scales batch calculations instantly
- Tracks true costs per candle as material prices change
Start your 14-day free trial—no credit card required.
Key Takeaways
- Fragrance load = percentage of fragrance oil in your total candle weight
- Start at 6% (1 oz per 1 lb wax) and increase in 0.5-1% increments as needed
- Most waxes handle 6-10% fragrance; soy maxes at 10%, coconut can go to 12%
- Always weigh fragrance on a scale—never measure by volume
- Add at 185°F and stir for 2 full minutes for optimal binding
- Cure soy candles 1-2 weeks before evaluating scent throw
- Weak scent throw isn't always a fragrance load problem—check wick size, temperature, and cure time first
- Wax capacity is your limit for candles, not IFRA
Ready to automate fragrance calculations across all your recipes?
PetalMade handles the math so you can focus on creating candles customers love.
Important Disclaimer
This guide provides general educational information only. You are solely responsible for product safety testing, regulatory compliance in your jurisdiction, proper insurance coverage, and consulting qualified professionals when needed. Starling Petals LLC is not liable for any injuries, damages, or losses resulting from the use of this information. See our Terms of Service for details.
Ready to put this into practice?
PetalMade helps you manage your products, ensure IFRA compliance, and grow your maker business.
Start Your Free Trial