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HLB Calculator
Find the perfect emulsifier blend for your oil phase. Enter your oils, pick your emulsifiers, and get instant blend ratios with match-quality scoring.
Oil Phase
%
%
Total: 25.0%
g
%
Emulsifier Pair
Required HLB
7.6
Intermediate
May be unstable - consider adjusting oil blend or using co-emulsifiers
Emulsifier Blend
Exact MatchSpan 60 (Sorbitan Stearate)
HLB 4.7
71.6%
Tween 60 (Polysorbate 60)
HLB 14.9
28.4%
Achieved HLB7.60
HLB Scale (0 - 20)
7.6
- Lipophilic 0–3
- W/O 3–6
- Wetting 6–9
- O/W 9–13
- Detergent 13–15
- Solubilizer 15–18
- Hydrophilic 18–20
This calculator uses published HLB values. Always verify with stability testing. Formuley tracks HLB values for 200+ oils automatically.
What is HLB?
The Hydrophilic-Lipophilic Balance (HLB) system is a scale from 0 to 20 that classifies surfactants and emulsifiers based on their relative attraction to water versus oil. A value near 0 is completely lipophilic (oil-loving), while a value near 20 is completely hydrophilic (water-loving).
Developed by William C. Griffin in 1949, the HLB system is one of the most reliable methods for selecting emulsifiers in cosmetic formulation. Every oil has a “required HLB” — the HLB value an emulsifier system must achieve to create a stable emulsion with that oil.
To formulate with the HLB system, you calculate the weighted-average required HLB of your oil phase, then blend two emulsifiers (one low-HLB and one high-HLB) in the ratio needed to hit that target. This pairing approach produces more stable emulsions than using a single emulsifier.
HLB Ranges & Applications
| HLB Range | Application |
|---|---|
| 3 - 6 | W/O Emulsifiers |
| 7 - 9 | Wetting Agents |
| 8 - 18 | O/W Emulsifiers |
| 13 - 15 | Detergents |
| 15 - 18 | Solubilizers |
How to Choose Emulsifiers
The most reliable approach is the HLB pairing method. Instead of searching for a single emulsifier that matches your required HLB exactly, you blend two emulsifiers: one with a low HLB value and one with a high HLB value.
1
Calculate Required HLB
Find the weighted average of the required HLB values for every oil in your formula, based on their percentages in the oil phase.
2
Pick a Low + High Pair
Choose one emulsifier below the required HLB (e.g., Span 60 at 4.7) and one above (e.g., Tween 60 at 14.9). The pair should bracket your target value.
3
Calculate the Blend Ratio
Use the formula: % High = (Required HLB - Low HLB) / (High HLB - Low HLB) × 100. The remaining percentage is the low-HLB emulsifier.
Pro tip: Span/Tween pairs (e.g., Span 60 + Tween 60) are the classic go-to because they share the same fatty acid base, producing a tighter interfacial film. For conditioning emulsions, BTMS-50 paired with Ceteareth-20 is a popular choice.
Common Oils & Required HLB Values
| Oil / Butter | Required HLB |
|---|---|
| Mineral Oil | 10 |
| Castor Oil | 14 |
| Coconut Oil | 8 |
| Olive Oil | 7 |
| Jojoba Oil | 6.5 |
| Sweet Almond Oil | 7 |
| Shea Butter | 8 |
| Avocado Oil | 7 |
| Sunflower Oil | 7 |
| Grapeseed Oil | 7 |
| Apricot Kernel Oil | 7 |
| Argan Oil | 7 |
Values are approximate and sourced from published emulsifier supplier data. Formuley's database includes 200+ oils with verified HLB values.
Frequently Asked Questions
What does HLB stand for?
HLB stands for Hydrophilic-Lipophilic Balance. It is a numerical scale from 0 to 20 that describes the balance between the water-loving (hydrophilic) and oil-loving (lipophilic) parts of a surfactant or emulsifier molecule. The system was developed by William C. Griffin in 1949.
How do I find the required HLB for an oil?
The required HLB for an oil is determined experimentally by the oil manufacturer or through published reference tables. Each oil has a specific HLB value needed to form a stable emulsion. For example, Coconut Oil requires an HLB of 8, while Castor Oil requires 14. If you cannot find a published value, start with 7 for most vegetable oils and adjust based on stability testing.
Why use two emulsifiers instead of one?
Using a pair of emulsifiers (one with a low HLB and one with a high HLB) creates a more stable emulsion than using a single emulsifier at the same HLB value. The two emulsifiers form a mixed interfacial film around droplets that is more resistant to coalescence. This is known as the HLB system pairing method, and it produces emulsions with finer droplet sizes and longer shelf stability.
What happens if my HLB is wrong?
If the HLB of your emulsifier system does not match the required HLB of your oil phase, the emulsion will be unstable. You may see separation (oil floating on top or sinking), graininess, or the emulsion may break within hours or days. An HLB mismatch of more than 2 units is generally considered problematic. Small mismatches (under 1 unit) usually produce acceptable results.
What emulsifier percentage should I use?
A typical starting point is 3-6% total emulsifier for light lotions, 5-8% for creams, and 8-12% for heavy creams or products with a high oil phase. The exact amount depends on the ratio of oil to water, the specific emulsifiers used, and the desired texture. Always run stability tests to confirm your percentage is adequate.
Can I use HLB for silicones?
Silicones have different chemistry from traditional oils, and the standard HLB system does not always predict their behavior accurately. Dimethicone typically requires an HLB around 10-12, but many silicone-based emulsions use specialized silicone emulsifiers (like PEG-modified dimethicone) rather than traditional HLB-paired surfactants. For silicone-heavy formulas, consult your silicone supplier for specific emulsifier recommendations.
Inside Formuley
This Calculator, Supercharged
The free version is great for quick calculations. Inside Formuley, it connects to your entire emulsion workflow.
Auto-fill oil phases from your saved formulas
200+ oils with verified HLB values
Save emulsifier blend results to formula notes
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Batch scaling with emulsifier recalculation
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