Need to know whether that hot skillet dish fits your fat budget? The Hot Fat Per 100g Calculator converts the total fat in a cooked batch into a clean per-100g number — the same format used on nutrition labels. Just enter the total fat and the final cooked weight of your dish, and you'll instantly see fat per 100g, energy from fat, fat per serving, and (if you provide total calories) the percentage of calories coming from fat.
This tool is built for home cooks, meal preppers, and anyone tracking macros or calories. Hot, freshly cooked food weighs differently than raw ingredients because water evaporates and fat renders out, so using the cooked weight is the key to realistic numbers. You can also use the optional serving-size field to see fat per portion, and the quick presets give you realistic starting points for dishes such as pan-seared salmon, home fries, and chicken thighs.
🍳 Batch Details
Optional Details
Leave blank to skip per-serving results.
Optional – needed for the % calories from fat result.
📊 Results
Step-by-step
Step-by-Step Guide
Start by weighing the entire cooked dish in grams on a kitchen scale — include pan drippings, sauce, or juices if you plan to eat them, because they carry a large share of the fat. Next, work out the total fat in the batch. If you cooked from packaged ingredients, read the nutrition labels and add up the fat grams. If you used a recipe app or a food database such as USDA FoodData Central, choose the cooked preparation for each ingredient and sum the values. Enter both numbers, then optionally add a serving size and the total batch calories.
- Enter the total grams of fat for the whole cooked batch.
- Enter the total cooked weight of the batch in grams.
- Optional: enter a serving size in grams to see fat per portion.
- Optional: enter the total calories in the batch to see the calories-from-fat percentage.
- Press Calculate and read the per-100g results.
The quick preset buttons load realistic example values so you can see how the result formats work before entering your own dish. Use them as a starting point, then replace the numbers with your measured values.
How It Works
Fat per 100 g is simply the proportion of the food's mass that comes from fat, scaled to the standard 100 g reference portion used on nutrition labels. If a 300 g dish contains 21 g of fat, then every 100 g portion contains 7 g, because 21 ÷ 300 × 100 = 7.
To estimate the energy that fat contributes, the calculator uses the Atwater general factor of 9 kcal per gram of fat — the conventional figure used in food labelling, alongside 4 kcal per gram for protein and carbohydrate. It is an average across the common fatty acids, so it is accurate enough for everyday macro tracking but not perfectly precise for unusual fats such as MCT oil.
Energy from fat per 100 g = fat per 100 g × 9 kcal/g
Fat per serving = fat per 100 g × serving size ÷ 100
% of calories from fat = (total batch fat × 9 ÷ total batch calories) × 100
Worked Examples
Factors Affecting Accuracy
A few real-world factors can change the numbers from one meal to the next:
- Added oil and butter. Every tablespoon of olive oil adds about 14 g of fat to a dish, so cooking fat often dominates the batch total.
- Rendering and drip loss. Fat that drips off and is not eaten should not be counted. Weigh the dish as served to reflect what actually reaches the plate.
- Moisture loss. Evaporation concentrates nutrients per gram, which is why cooked meat always shows higher fat per 100 g than the raw version.
- Database variation. Food composition values differ slightly by breed, cut, and cooking method, so treat published numbers as estimates.
Reference Data
These typical cooked values help you sanity-check your results. Exact numbers vary with method and added fat.
| Food (cooked) | Typical fat per 100 g |
|---|---|
| Skinless chicken breast, roasted | ~3–4 g |
| Skinless chicken thigh, roasted | ~8–10 g |
| Atlantic salmon, baked | ~10–13 g |
| 80% lean beef patty, grilled | ~18–20 g |
| Roasted potatoes with oil | ~5–7 g |
| Fried egg in butter | ~9–11 g |
For precise values, look up the specific food and preparation method in USDA FoodData Central.
Frequently Asked Questions
Why per 100 g instead of per serving? Per-100g values are the universal nutrition-label format, so they make it easy to compare different foods and to scale results to any serving size that fits your meal plan.
Should I enter fat from raw or cooked ingredients? Prefer cooked values whenever they are available. Raw ingredients lose water during cooking, so raw-based calculations understate the fat per 100 g of the finished dish. Most nutrition databases list a cooked preparation option for meat and vegetables.
Does 9 kcal per gram apply to every fat? It is the standard Atwater factor used for labelling worldwide. Common cooking oils and animal fats sit close to this value, although a few specialty fats differ slightly.