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Cycling Nutrition Calculator
Upload your GPX route for an hour-by-hour cycling fuel plan.
Climbs get more fuel, descents less, based on your route's actual power demands. Or use Quick Mode for an instant estimate from ride duration and intensity. Either way: carbs, gels, fluid, sodium, and calories — for sportives, gran fondos, and long training rides. A GPX nutrition plan that respects gradient, surface type, and rider weight.
How much should you eat while cycling? For moderate-intensity rides, consume 40–60 g of carbohydrates per hour, drink 500–750 ml of fluid per hour, and replace 500–700 mg of sodium per hour. For high-intensity or racing, increase to 80–120 g carbs/h (requires gut training). Adjust for temperature: add 30–50% more fluid in hot conditions (over 25 °C). This calculator gives personalized targets based on your ride duration, intensity, weather, and gut training level — or upload a GPX file for hour-by-hour fuel targets that account for climbs and descents.
Updated for 2026 · Based on Jeukendrup carbohydrate absorption research and current World Tour nutrition protocols.
Inputs
Intensity
Temperature
Gut training
Gut training takes 2–3 weeks of consistent practice. Many amateurs try 90g/h but their gut can't handle it — GI distress on race day.
Nutrition plan for 2h at moderate intensity
Pack equivalents
Starting point based on rider weight and intensity. Practise fueling in training — never test new nutrition on race day. For routes with significant climbing, switch to the GPX Route Planner tab for hour-by-hour breakdown.
How the calculation works
What is a cycling nutrition plan?
A cycling nutrition plan is a structured schedule of carbohydrate, fluid and electrolyte intake for a specific ride, broken down hour by hour. Unlike generic sports nutrition advice, a route-specific plan accounts for the actual power demands of each section of the ride — steeper climbs burn significantly more kilojoules than flat sections at the same speed.
This calculator uses a physics-based power model derived from your GPX file. It calculates the mechanical power required at each GPS point using speed, gradient, rider mass, bike mass, air resistance and rolling resistance. The power output is then converted to kilojoules of mechanical energy and to kilocalories of metabolic energy (applying a 23–25% mechanical efficiency factor). Carbohydrate intake targets are set at 60–90 g per hour depending on effort level, with gel equivalents provided for easy on-bike reference.
The plan is designed for endurance cycling events: gran fondos, sportives, ultra-distance rides, gravel races, and long training rides. It is not designed for criteriums, track cycling, or efforts under 60 minutes where pre-ride glycogen loading is typically sufficient.
Who needs a cycling nutrition calculator?
This tool is used by amateur cyclists preparing for their first gran fondo who want to know how many gels and bottles to carry, by experienced riders who have bonked (run out of glycogen) on long rides and need a more structured approach, by coaches building nutrition protocols for athletes, by adventure cyclists on multi-day bikepacking routes where resupply planning matters, and by anyone riding a route with significant elevation gain where the caloric cost differs substantially from a flat-road estimate.
Cycling Nutrition Guide — Carbs Per Hour by Intensity
Reference for carbs per hour cycling at different intensities, plus matching gel count and fluid recommendations.
| Intensity | Carbs/Hour | Gels/Hour | Fluid/Hour | Example Ride |
|---|---|---|---|---|
| Easy (Zone 2) | 30–40 g | 1–1.5 | 400–500 ml | Recovery spin, easy endurance |
| Moderate (Zone 3) | 50–60 g | 2–2.5 | 500–600 ml | Group ride, tempo intervals |
| Hard (Zone 4) | 60–80 g | 2.5–3 | 600–750 ml | Sportive, threshold training |
| Race (Zone 4–5) | 80–120 g | 3–5 | 700–1000 ml | TT, crit, climbing race |
Modern sports science supports up to 120g carbs/hour using dual-transport carbohydrates (glucose + fructose in 1:0.8 ratio). Start at the lower end and practice fueling in training — never try a new nutrition strategy on race day.
How Many Gels Do I Need? — Quick Lookup
Fast answer to how many gels for cycling, by ride duration and intensity.
| Ride Duration | Easy | Moderate | Hard |
|---|---|---|---|
| 1 hour | 0–1 gel | 1–2 gels | 2–3 gels |
| 2 hours | 2–3 gels | 4–5 gels | 5–6 gels |
| 3 hours | 3–4 gels | 6–7 gels | 8–10 gels |
| 4 hours | 4–6 gels | 8–10 gels | 10–12 gels |
| 5 hours | 6–8 gels | 10–12 gels | 12–15 gels |
| 6+ hours | 8–10 gels | 12–15 gels | 15–18 gels |
Mix gels with bars, bananas, and drink mix for variety. Do not rely on gels alone for rides over 3 hours — stomach fatigue is real. 1 gel ≈ 25g carbs, 1 bar ≈ 40g carbs, 1 banana ≈ 25g carbs.
When to Start Eating on a Bike Ride
Start eating at the 45–60 minute mark for any ride over 90 minutes. For rides under 1 hour, water alone is usually sufficient — your body has enough stored glycogen (~1,800–2,000 kcal). The key rule: eat before you are hungry, drink before you are thirsty. Your body can absorb about 60–90 g of carbs per hour from standard sources, or up to 120 g with dual-transport formulas (glucose + fructose). Waiting until you feel hungry means you are already depleted — bonking recovery takes 20–30 minutes even after eating, and performance drops significantly. Planning an e-bike ride? Check your battery will last with our e-bike range calculator — running out of battery AND bonking is no fun.
Carbs Per Hour — The Science
Most cyclists need 40–60 g of carbohydrates per hour for moderate rides and 80–120 g/h for racing — but your gut must be trained to handle the higher amounts. Start at 40 g/h and increase by ~10 g/h per week. The 60–90 g/hour recommendation comes from decades of exercise physiology research: single-transport carbs (glucose only) max out at ~60 g/h due to the SGLT1 intestinal transporter, while dual-transport carbs (glucose + fructose, typically 1:0.8 ratio) recruit the GLUT5 transporter and push absorption to 90–120 g/h. Brands like Maurten, SiS Beta Fuel and Precision Fuel use this approach. For most recreational cyclists 40–60 g/h is plenty; competitive riders benefit from training the gut to 80–120 g/h. Edit your route before uploading with our GPX editor, and track training load with our ACWR calculator to avoid overtraining while fueling properly.
Why This Cycling Nutrition Calculator Is Different
This is the only free cycling nutrition calculator that accepts GPX files and calculates fuel targets segment by segment — more carbs on climbs (where energy demand is 3–4× higher than flat riding at the same speed), less on descents. It also adjusts for temperature (hotter weather = +30–60% fluid and sodium) and gut training level (untrained guts can only absorb ~40 g/h, pushing higher causes GI distress). Most other calculators output a single flat number like "60 g carbs per hour" regardless of terrain — useful as a baseline, but a flat 100 km ride and a mountainous 100 km ride have completely different energy demands. Your cycling fuel plan should reflect that, and a GPX nutrition plan tailored to your specific ride is what this tool delivers.
Cycling Sodium Intake — Why It Matters
Replace 500–700 mg of sodium per hour in moderate cycling conditions, 600–900 mg/h in heat (over 25 °C), and up to 1200 mg/h for heavy sweaters in very hot conditions. Sweat sodium concentration ranges from 200 to 2000 mg per litre depending on genetics, fitness and acclimatisation. Cycling sodium intake is the third pillar of nutrition most amateurs ignore. Drinking plain water on a 4-hour ride without sodium dilutes blood sodium and causes cramping, brain fog, and (rarely) hyponatraemia. The calculator above adjusts your sodium target by intensity and temperature. Practical sources: SiS GO Electrolyte (~500 mg per sachet), Precision Hydration PH1000 (1000 mg per tab), salty foods (pretzels, salted nuts), or an electrolyte capsule like Salt Stick.
Gut Training for Cycling — Why 90 g/h Fails Without It
Untrained cyclists can absorb about 40 g of carbohydrate per hour; trained guts handle up to 120 g/h. The difference comes from intestinal transporter density and gastric emptying, both of which adapt with deliberate practice. Gut training cycling is the deliberate practice of consuming more carbs per hour during training rides to expand absorption capacity. Untrained riders who suddenly try 90 g/h on race day get GI distress (bloating, cramps, urgent toilet stops, vomiting). The gut adapts in three ways: more transporter proteins, better gastric emptying, and tolerance to high-osmolality drinks. Protocol: pick a baseline you tolerate easily (often 40–50 g/h), add 10 g/h every 7–10 days on long rides, and use a mix of glucose and fructose (Maurten, SiS Beta Fuel, etc.). Over 6–8 weeks most riders move from 50 g/h to 90 g/h with no GI issues. The gut training input above caps the recommendation so you don't accidentally plan for absorption you don't have yet.
Frequently asked questions
How many carbs per hour for cycling?
For most cyclists, 40–60g of carbs per hour is a good target for moderate-intensity rides. For hard efforts and racing, aim for 60–90g/hour. Elite cyclists using dual-transport carbohydrates can absorb up to 120g/hour. Start at the lower end and increase gradually — gut training takes 2–3 weeks of consistent practice.
How much should I drink while cycling?
Aim for 500–750ml of fluid per hour in moderate conditions. In hot weather (above 30°C), increase to 750–1000ml/hour. A good rule: one standard cycling bottle (500ml) per hour at minimum. For rides over 2 hours, use electrolyte drink mix rather than plain water to replace sodium lost through sweat.
Do I need to eat on a 1-hour ride?
Generally no. Your body stores about 400–500g of glycogen (1600–2000 kcal), which is enough for 60–90 minutes of moderate cycling. For rides under 1 hour, water is sufficient. For rides of 60–90 minutes at high intensity, a gel in the last 20 minutes can help. Fueling becomes important for rides over 90 minutes.
What is the difference between gels, bars, and drink mix?
Gels are fast-absorbing (25g carbs in 30ml), ideal during hard efforts when chewing is difficult. Bars (40g carbs) are slower-absorbing but more satisfying for long rides. Drink mix (30g carbs per 500ml) provides both carbs and hydration simultaneously. For best results, mix all three: drink mix as a base, gels for intense moments, bars for steady fueling.
How many gels do I need for a 100 km ride?
Typically 8–10 gels for a flat 100 km ride at moderate pace, 12–16 gels for a hilly 100 km with 2,000 m of climbing. A flat 100 km ride at moderate pace takes approximately 3–3.5 hours and burns around 1,800–2,200 kcal. At 60 g carbohydrate per hour you need 8–10 gels (each 25 g carbs) or equivalent. A hilly 100 km ride with 2,000 m of climbing can take 4.5–6 hours and burn 3,000–4,000 kcal, requiring 12–16 gels. Upload your GPX file (GPX Route Planner tab above) to get an exact figure for your specific route. For triathlon nutrition planning across swim, bike and run, try our triathlon split calculator.
What is the 60–90 g carbohydrate per hour rule?
Research shows the gut can absorb approximately 60 g of glucose per hour. Combining glucose and fructose in a 2:1 ratio increases absorption to 90 g per hour because they use different intestinal transporters. Most energy gels contain 20–25 g of carbohydrates. For efforts over 2.5 hours at high intensity, targeting 60–90 g/hour is the current sports science consensus for endurance performance.
How does the power model calculate calorie burn?
The calculator reads your GPX elevation data and estimates the mechanical power needed at every GPS point — accounting for three forces: air resistance (which grows with the cube of your speed), rolling resistance (surface and weight), and climbing (gradient and mass). Power in kilojoules converts to food calories at roughly a 1:1 ratio, which is the standard used by Garmin, TrainerRoad and Stages.
What is bonking and how does nutrition prevent it?
Bonking (or "hitting the wall") is the sudden onset of extreme fatigue caused by depleted glycogen stores. Glycogen is the primary fuel for high-intensity cycling, stored in muscles and the liver. A trained cyclist stores approximately 1,800–2,000 kcal of glycogen — enough for roughly 90 minutes at race pace. Consuming carbohydrates during the ride extends this supply indefinitely. Missing nutrition intake for even one hour at high effort can lead to bonking on a long ride.
How much water should I drink on a long ride?
A general guideline is 500–750 ml per hour in moderate temperatures, and 750–1,000 ml per hour in hot conditions above 25°C. Electrolyte loss (sodium, potassium) becomes significant in rides over 2 hours and in high-sweat conditions. Add electrolyte tablets or drink sports drinks rather than plain water on rides exceeding 2 hours to avoid hyponatraemia (low sodium from overdrinking plain water).
Should I eat differently for a hilly route versus a flat route?
Yes. Climbs dramatically increase power output — a 6% grade at 15 km/h requires roughly 3–4× more power than flat riding at the same speed. The caloric cost of climbing is therefore much higher per minute. On a hilly route, you need to eat more in total and time your intake before major climbs, as the gut is less efficient at absorbing nutrition during very high-intensity efforts.
Can I use this calculator for a mountain bike or gravel ride?
Yes. Select the surface type in the form — Road, Gravel, MTB or Cobbles. Each surface applies the correct rolling resistance and an energy multiplier for body movement and terrain difficulty: Gravel adds 15%, Cobbles 20%, and MTB 28% to the base energy cost. The plan automatically adjusts.
How does elevation gain affect calorie burn?
Climbing adds a direct gravitational power requirement. Every 100 m of altitude gained burns approximately 30 kcal per 10 kg of combined rider and bike weight (from P = mgh). A 75 kg rider on a 9 kg bike climbing 1,000 m of total elevation burns an additional 250–300 kcal from climbing alone, on top of the baseline cost of moving through air and overcoming rolling resistance. The GPX elevation profile is used to calculate this precisely for your specific route.
How many gels do I need for a 50 km ride?
3–5 gels for a 50 km ride at moderate pace. A flat 50 km ride takes about 1.5–2 hours and burns 900–1,200 kcal. At 60 g/h you need 3–4 gels (each 25 g carbs). For hilly 50 km routes with 1,000 m of climbing, plan 5–7 gels because the climbing increases caloric cost significantly. For shorter sub-60-minute rides, gels are optional.
How much more should I drink in hot weather?
Increase fluid intake by 30% in hot conditions (25–35 °C) and 60% in very hot conditions (over 35 °C). So if you normally drink 600 ml/h at moderate intensity, that becomes about 780 ml/h in heat and 960 ml/h in extreme heat. Sodium target also rises by the same percentages. The Quick Calculator above has a Temperature input that does this adjustment for you.