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Open-Source Endurance Fuel
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The simplest formulas
that actually work.

You don't need 12 ingredients. You don't need proprietary blends. Here are the bare-minimum formulas — sourced from Amazon — that match or beat most commercial products.

The real "secret" is just three variables
Carb ratio (2:1) · Total carb intake per hour · Sodium dosing. Everything else in commercial products is flavour, texture, and branding.
1
Carb Drink Mix

Performance-Focused, Minimal

Formula — Per Serving
Maltodextrin
60 g
Primary carb source
Fructose
30 g
Secondary carb source
Sodium (as sodium citrate)
600–800 mg
Electrolyte / absorption
Water
500–750 mL
Carb Ratio
2:1
Total Carbs
90 g
Rate
~90 g/hr
Est. Cost
~$0.93
+$0.11 flavoring
Why This Works
2:1 glucose:fructose ratio → maximizes carb oxidation at 90 g/hr+
Maltodextrin = low osmolality → easier on the gut than straight glucose
Sodium citrate > table salt → less GI distress at high sodium doses
Amazon Sources
2
Carb Gel

DIY, Minimal Ingredients

Formula — Per Serving
Maltodextrin
40 g
Fructose
20 g
Water
20–30 g
Just enough for gel consistency
Sodium Citrate
200–300 mg
Optional — adds ~55–80 mg Na
Carb Ratio
2:1
Total Carbs
60 g
Serving Wt.
~85 g
Est. Cost
~$0.62
+$0.11 flavoring
Why This Works
Same 2:1 ratio as the drink mix, just more concentrated
High carb density — up to 60 g per gel possible
No gums, no fillers → simpler digestion (always chase with water)
Amazon Sources
3
Electrolyte Mix

Clean Hydration

Formula — Per Serving
Sodium citrate
1.5–2 g
~400–600 mg sodium
Potassium chloride
200–300 mg
Intracellular balance
Magnesium glycinate
100 mg
Muscle + cramp support
Water
500–750 mL
No sugar. Stack with the carb mix or gels when you also need fuel.
Why This Works
Sodium = primary driver of hydration and fluid retention
Potassium = intracellular electrolyte balance
Magnesium = muscle function and cramp mitigation
Amazon Sources
Key Takeaways

What actually matters vs. what you're paying for

✓ What actually works
2:1 glucose:fructose ratio (or 1:0.8 for higher ceiling)
Total carb intake per hour (60–120 g/hr depending on event)
Sodium dosing matched to your sweat rate
2–3 core ingredients is enough to match elite products
→ What you pay for in brands
Flavour systems (citric acid + natural flavor)
Texture agents (xanthan gum, pectin)
Branding and packaging markup
Proprietary blend mystery ratios
Optional Upgrades

Next-level optimisations (still simple)

1
Swap to 1:0.8 ratioCarb Mix + Gel

Slightly more fructose than 2:1 → higher exogenous oxidation ceiling at 90–120 g/hr

2
Add sodium alginate (small %)Carb Mix

Hydrogel-forming agent → may improve gut tolerance at high carbohydrate doses in some athletes

3
Add a flavour systemAll products

Citric acid (tartness) + natural flavour powder → makes large volumes far more palatable

These formulas are for educational and informational purposes only. Always test formulas in training before race use. Athletes are responsible for anti-doping compliance — verify ingredient sources. This is not medical advice. Read full disclaimer →

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