Carbohydrate Calculator

Estimate your recommended daily carbohydrate intake from your calorie needs. Free, instant, no signup.

How to use the Carbohydrate Calculator

  1. Enter your values. Fill in the fields with your numbers.
  2. Calculate. Press Calculate to run the carbohydrate calculator.
  3. Use the result. Copy the result or try a related tool next.

Why use our Carbohydrate Calculator

Instant results. Enter your figures and the carbohydrate calculator returns an answer in seconds.
Free & private. Runs in your browser — no signup, and nothing is sent to a server.
Accurate. Uses standard formulas so you can rely on the numbers.

Free to use — premium coming soon

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About the Carbohydrate Calculator

The Carbohydrate Calculator estimates how many grams of carbs you should eat each day to match your body and goals. Instead of guessing, it works from your real numbers: sex, age, height, weight, and activity level. From these it finds your daily calorie needs, decides what share of those calories should come from carbohydrates, and converts that figure into grams. The result is a concrete daily target you can carry into a food diary, a meal-planning app, or a nutrition label, rather than a vague rule of thumb like 'eat fewer carbs'.

Reach for this tool when you are planning meals, dialling in a fitness goal, or simply curious whether your current eating fits dietary guidelines. Endurance athletes use it to fuel training, people watching their weight use it to set a deficit, and anyone learning to read nutrition labels uses it to put a number on 'carbs per day'. It is also handy for splitting calories across the three macronutrients, since carbohydrate, protein, and fat targets all have to add up to your total energy intake.

Under the hood it follows the same method dietitians use. It estimates your Basal Metabolic Rate with the Mifflin-St Jeor equation, multiplies that by an activity factor to get your Total Daily Energy Expenditure, and then applies a carbohydrate percentage of those calories. The Acceptable Macronutrient Distribution Range puts that share at 45 to 65 percent of total calories. Because each gram of carbohydrate supplies 4 calories, the calculator divides your carb calories by 4. For example, 50 percent of a 2,000-calorie day is 1,000 calories, which is 250 grams of carbohydrate.

Treat the result as a well-founded estimate, not a medical prescription. The Mifflin-St Jeor formula and the AMDR are population averages, so your real needs can shift with metabolism, muscle mass, health conditions, and how hard you actually train. The calculator runs entirely in your browser, so the height, weight, and age you enter are never uploaded or stored on a server. If you manage diabetes, pregnancy, or another condition, use the numbers as a starting point and confirm your targets with a doctor or registered dietitian.

Frequently asked questions

How many grams of carbs should I eat per day?

It depends on your calorie needs. The Acceptable Macronutrient Distribution Range puts carbohydrates at 45 to 65 percent of total calories, so a 2,000-calorie diet works out to roughly 225 to 325 grams per day. The calculator finds your own calorie level first, then converts the chosen percentage into grams.

What formula does this carbohydrate calculator use?

It estimates Basal Metabolic Rate with the Mifflin-St Jeor equation, multiplies by an activity factor to get total daily calories, applies a carbohydrate percentage (45 to 65 percent), then divides by 4 because each gram of carbohydrate contains 4 calories.

What is the minimum amount of carbohydrate I need?

The Food and Nutrition Board sets the Recommended Dietary Allowance for carbohydrates at 130 grams per day for adults and children. That figure reflects the minimum needed to supply the brain with glucose, and it is generally below most calorie-based targets.

Does this give me net carbs or total carbs?

It gives a total carbohydrate target. Net carbs are a separate concept used on food labels, where fiber and some sugar alcohols are subtracted from total carbs. To track net carbs, count your foods normally and subtract their fiber from the total.

How accurate is the result for me?

It is a solid estimate based on population averages, not a personalised measurement. Your true needs vary with metabolism, muscle mass, training load, and health status, so use the number as a starting point and adjust based on real-world results.

From our blog

How to Calculate Your University Grade by Credits (and Hit the Classification You Want)

By the Super Simple Digital Tools Team · Updated June 2026

The single biggest mistake students make when estimating their degree grade is taking a simple average of their module marks. Universities almost never work that way. They use a credit-weighted average, which means a module's influence on your final percentage is proportional to how many credits it carries. A 40-credit project counts four times as much as a 10-credit module, so averaging them as equals can throw your estimate off by several percent and even put you in the wrong classification band.

To do it correctly, list every module with two figures: the mark you achieved and the number of credits it is worth. Multiply each mark by its credits, add up all those products, and divide by the total credits. For example, marks of 68%, 72% and 55% in modules worth 20, 20 and 10 credits give (68x20 + 72x20 + 55x10) divided by 50, which works out to 67.4% overall. A full-time year in the UK is usually 120 credits, so your year average should be built from modules that add up to that total.

If your degree weights academic years differently, add one more step. Work out the average for each year on its own using the credit method above, then combine the years with their weightings. A widespread pattern is Year 2 contributing 40% and Year 3 contributing 60%, with Year 1 contributing nothing beyond the requirement to pass it. So a 64% second year and a 70% final year produce an overall of 64x0.40 plus 70x0.60, which is 67.6%, comfortably a 2:1 and within striking distance of a First.

Once you have your running average, the calculator becomes a planning tool. Suppose you are sitting on 67% with one 30-credit module left and the rest of your degree fixed. You can plug in different marks for that final module to see exactly what score lifts your overall figure to 70%. This turns a vague hope of getting a First into a concrete target, letting you direct your revision time where it will actually move the needle rather than spreading effort evenly across everything.

Finally, treat the output as a well-informed estimate rather than gospel. Institutions differ on rounding (some round only the final number, some never round up across a boundary), on whether resit marks are capped, and on how borderline cases are reviewed. The calculation itself is exact, but the rules wrapped around it are set by your university. Use the tool to plan and to check your own working, then confirm the official figure against your handbook or transcript before making any decisions that depend on it.

  • Always enter the real credit value for each module (10, 15, 20, 30 and so on); using equal weights silently distorts your average.
  • Round only the final overall percentage, never the individual module marks, so early rounding does not push you across a classification boundary.
  • To find the mark you still need, lock in your completed modules and increase the outstanding module's score until the average hits your target band.
  • If your degree weights years, average each year separately first, then apply the year weightings (for example 40% Year 2 plus 60% Year 3).

Read the full guide →

Tool by the Super Simple Digital Tools Team. Reviewed by our editorial team. Free to use, no signup required.

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