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79 reviewed tools
Original diagram of total 25-hydroxyvitamin D blood unit conversion between ng/mL and nmol/L using 2.496.FreeBlood results

Vitamin D Blood Unit Converter

Convert total 25-hydroxyvitamin D blood results between ng/mL and nmol/L using the declared 2.496 factor. Units only, without result classification or doses.

Open toolZinc unit conversion example: 10.00 µmol/L becomes 65.38 µg/dL after multiplying by 6.538.FreeBlood results

Zinc unit converter

Convert zinc between µmol/L and µg/dL using the declared factor 6.538. Check rounding, units and report limits without interpreting a result or calculating a dose.

Open toolOriginal arithmetic diagram: 500 grams of total flour is 100 percent and 350 grams of water is 70 percent of that flour mass.FreeWeight and nutrition

Baker's Percentage Calculator

Calculate one ingredient as a percentage of total flour weight. Clear gram inputs, worked examples, two-decimal rounding and no account required.

Open toolFreeWeight and nutrition

BMI calculator: adult BMI and reference chart

Calculate adult BMI in metric, pounds or stone, see height-specific reference points, and understand the result's limits. Free, private and evidence-based.

Open toolOriginal diagram of a drink beside caffeine milligrams divided by matching drink volume in millilitres, multiplied by 100 to give mg per 100 ml.FreeWeight and nutrition

Caffeine per 100 ml calculator

Convert matching labelled caffeine milligrams and drink volume in millilitres into mg per 100 ml. Free, private concentration arithmetic with no safe-dose verdict.

Open toolWorked food-label example: 150 kcal in 30 g becomes 500 kcal per 100 g.FreeWeight and nutrition

Calories per 100 g calculator

Convert calories and gram weight from the same labelled portion into kcal per 100 g. Free calculator with a worked example, label checks and no intake target.

Open toolFreeWeight and nutrition

Calories per meal calculator

Split a daily calorie or kilojoule amount equally or by your own percentages. Whole-number meal results always add back to your exact total.

Open toolIllustrative carbohydrate scaling diagram: 18 grams in 40 grams of food becomes 45 grams per 100 grams; both bars keep the same 45 percent proportion.FreeWeight and nutrition

Carbohydrate per 100 g Calculator

Convert labeled carbohydrate per serving to grams per 100 g using the matching serving weight. Clear examples, two-decimal rounding and no account required.

Open toolOriginal length diagram with matching endpoints for one international inch and 2.54 centimetres, showing the exact relationship on an illustrative scale.FreeWeight and nutrition

Centimetres and Inches Converter

Convert a known length between centimetres and inches using exactly 1 inch = 2.54 cm. Both directions, clear rounding and private browser-memory calculation.

Open toolSynthetic package price of 24.00 divided by eight labelled servings gives 3.00 per serving in the same currency; four servings are illustrated.FreeWeight and nutrition

Cost per Serving Calculator

Divide a known package price by its matching serving count, including fractions. Keep the same currency and compare serving sizes; no portion or dose advice.

Open toolFreeWeight and nutrition

Daily calorie needs calculator: energy requirement and resting estimate

Estimate adult daily energy with the 2023 DRI equation and see a separate Mifflin–St Jeor resting estimate in kcal and kJ.

Open toolExample label arithmetic: 4 g fibre divided by a matching 28 g reference gives 14.3% after rounding; this is not a personal target.FreeWeight and nutrition

Percent Daily Value calculator

Calculate a nutrient amount as a percentage of a supplied Daily Value. Check matching units and servings, with clear examples and no account required.

Open toolTwo clocks joined by a day-to-night timing arc beside an empty plateFreeWeight and nutrition

Fasting window calculator

Calculate the exact time between your last and next calories, or work out when a fasting window ends. Neutral clock arithmetic with no protocol advice.

Open toolInvented food-label example: 6 g dietary fiber and 200 kcal from one serving equals 3.00 g fiber per 100 kcal.FreeWeight and nutrition

Fiber per 100 calories calculator

Calculate dietary fiber per 100 calories from matching food-label values. Compare the ratio, see worked examples and understand its limits. Free and private.

Open toolSynthetic fibre label example: 4 g fibre in 40 g food scales to 10 g per 100 g; a comparison, not a real product or intake target.FreeWeight and nutrition

Fibre per 100 g Calculator

Convert dietary fibre in a matching food serving to grams per 100 g. Compare like labels with exact arithmetic, clear limits and private browser inputs.

Open toolOne US fluid ounce is 29.57 mL and one Imperial fluid ounce is 28.41 mL after rounding; volume units are kept distinct from mass.FreeWeight and nutrition

Fluid ounces to mL converter

Convert US or Imperial fluid ounces to millilitres and back. Choose the correct system, see exact factors and understand food-label rounding differences.

Open toolMass conversion diagram: one avoirdupois ounce equals exactly 28.349523125 grams, with two arrows around an unmarked kitchen scale.FreeWeight and nutrition

Grams and Ounces Converter

Convert grams to avoirdupois ounces or ounces to grams using the exact mass definition. Clear rounding, unit limits and examples, with no account required.

Open toolWorked grocery example: a pack price of 3.60 and weight of 300 g gives 1.20 per 100 g in the same currency.FreeWeight and nutrition

Grocery unit price calculator

Convert a grocery pack price and net weight into price per 100 g. Compare the same currency and weight basis, with clear examples and no account required.

Open toolFreeWeight and nutrition

Kilograms to pounds converter

Convert one body-weight or training-weight value between kilograms (kg) and international avoirdupois pounds (lb), without judging the weight or calculating a dose.

Open toolFreeWeight and nutrition

Kilojoules to calories converter

Convert food energy between kilojoules (kJ) and kilocalories (kcal) using the exact 4.184 factor, with clear units and private on-device calculation.

Open toolOriginal volume diagram with identical cubes labelled 1 L and 1,000 mL, showing multiplication and division by 1,000 for the same volume.FreeWeight and nutrition

Litres and Millilitres Converter

Convert litres to millilitres or back using exactly 1 L = 1,000 mL. Clear units, examples and rounding, with no account or personal fluid target.

Open toolOriginal mass-unit diagram showing 1 mg = 1,000 µg, three multiplication steps of ten and the reverse division by 1,000.FreeWeight and nutrition

Milligrams and Micrograms Converter

Convert milligrams to micrograms or back with the exact factor of 1,000. Clear unit labels, examples and rounding, with no account or dose recommendation.

Open toolInvented package example: price 30 and total labelled protein 600 g give a cost of 1.25 in the same currency per 25 g of protein.FreeWeight and nutrition

Protein cost calculator

Compare price per 25 g of labelled protein from a matching package or serving price and protein amount. See examples, currency limits and private local calculations.

Open toolInvented food-label example: 20 g protein and 200 kcal in the same serving gives 10.00 g protein per 100 kcal.FreeWeight and nutrition

Protein per 100 calories calculator

Calculate grams of protein per 100 calories from matching food-label values. See worked examples, serving-size checks and clear limits, with no account required.

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