MAFLD calculator
MAFLD is not a score, it is a definition with two halves: fat in the liver, plus metabolic dysfunction. This calculator checks both. It estimates the fat from your waist, your BMI, your triglycerides and your GGT, and checks the metabolic half against the three routes the definition allows.
Answer the questions on the left and your result will appear here.
The calculation runs in your browser and nothing you enter is sent to us or stored. The definition is a starting point for a conversation with a doctor, not a diagnosis.
The definition
What MAFLD is
MAFLD stands for metabolic dysfunction associated fatty liver disease. It was proposed in 2020 by an international panel to replace a name that had become a problem: non-alcoholic fatty liver disease, which defined a condition by what it was not.
The change is more than cosmetic. NAFLD was a diagnosis of exclusion: you got it once alcohol, hepatitis and everything else had been ruled out, which meant nobody could have a fatty liver from drinking and a fatty liver from metabolic dysfunction at the same time. MAFLD has positive criteria instead. It asks whether there is fat and whether there is metabolic dysfunction, and it does not care what else is also true.
So MAFLD is a label with a checklist, not a number on a scale. This page runs the checklist. The one part it cannot see directly is the fat, which is why it estimates that from four values a routine check-up already gives you.
The checklist
How the diagnosis is made
Two halves, both required. The first is evidence of fat in the liver, from a scan, a biopsy, or a blood-based score. The second is metabolic dysfunction, and there are three ways to satisfy it. Any one of them is enough, and more than one can apply at once.
The three metabolic routes
Overweight or obesity
BMI of 25 or more
The commonest route by a wide margin. A BMI of 25 or more satisfies the metabolic half on its own, with no blood value needed, which is why most people who meet the MAFLD criteria meet them here.
Type 2 diabetes
A diagnosis of type 2 diabetes
A diagnosis of type 2 diabetes satisfies the metabolic half at any weight, including a completely normal BMI. Fatty liver and type 2 diabetes travel together closely enough that the definition treats one as evidence of metabolic dysfunction outright.
Normal weight plus markers
BMI under 25, no type 2 diabetes, and two or more of the six markers below
The route for lean fatty liver, which is real and easy to miss. At a BMI under 25 without type 2 diabetes the definition asks for two or more separate signs of metabolic dysfunction, and it is the only route where the markers below decide anything.
The six metabolic markers
These decide the third route only, the one for a normal BMI without type 2 diabetes, and it needs two of them. Two are read from numbers this calculator already has: your waist and your triglycerides. The other four you tick.
| Marker | Counts when |
|---|---|
| Waist circumference | 88 cm or more for women, 102 cm or more for men |
| Blood pressure | 130/85 mmHg or higher, or you take medication for it |
| Triglycerides | 1.7 mmol/L or more |
| HDL cholesterol | Below 1.3 mmol/L for women, below 1.0 mmol/L for men, or you take medication for it |
| Prediabetes | HbA1c of 5.7 to 6.4 percent, or fasting glucose of 5.6 to 6.9 mmol/L |
| hs-CRP | Above 2 mg/L |
The published definition lists seven markers rather than six. The missing one is HOMA-IR, which needs a fasting insulin, and a Swiss check-up panel does not carry one. The triglyceride row is also read from your value alone, while the definition also counts anyone on treatment for it. Both gaps run the same way: they can only ever move a lean reader from meets the criteria to does not, never the reverse.
The fat estimate
How the fat half is estimated
When nobody has scanned your liver, this page uses the Fatty Liver Index, which the definition explicitly allows in place of imaging. It combines your waist, your BMI, your triglycerides and your GGT into a number from 0 to 100. A woman of 165 cm and 90 kg with a waist of 100 cm, triglycerides of 1.8 and a GGT of 40 scores 83.6, which rules fat in, and her BMI of 33.1 meets the metabolic half on its own, so she meets the criteria. Take her to 74 kg with a waist of 88 cm, triglycerides of 1.3 and a GGT of 28 and the index reads 40.4, which decides nothing.
| Index band | Fatty Liver Index | What it settles | Where it gets it wrong |
|---|---|---|---|
| Fat unlikely | below 30.0 | Below 30 the index rules fat out. It is the thing it does best: at this cut-off it misses roughly 13 in 100 fatty livers, so a low index is close to a clean answer without anyone scanning anything. | Misses about 13 in 100 fatty livers |
| Undecided | 30.0 to 59.9 | Between 30 and 60 the index has ruled nothing in and nothing out, and roughly a fifth of people land here. It is not a middling amount of fat, it is a missing answer, and an ultrasound is what supplies it. | Decides nothing either way |
| Fat likely | 60.0 and above | From 60 upwards the index rules fat in. It is less sure of itself in this direction: about 14 in 100 people who score here turn out not to have a fatty liver, so it is evidence rather than proof. | Wrongly flags about 14 in 100 clean livers |
The accuracy figures are from the population the index was built in: 496 people with an ultrasound to compare against, of whom 58 had a fatty liver. They are rates in a group, not the chance that your own result is wrong. The index is not a percentage and not an amount of fat: it is a rescaled likelihood, and 80 does not mean twice as much fat as 40.
What it reads
The things the checklist uses
Four measurements, two blood values, and two questions you can answer without either. Nothing here needs a scan, though a scan you have already had takes precedence over the estimate.
Waist circumference
The single most useful number on this page, and the one people get wrong. It is the heaviest term in the fat estimate, worth more over a realistic range than tripling your GGT, and it is also one of the six metabolic markers in its own right. Measure at the navel, not at your belt.
BMI
Your height and weight, combined. From 25 upwards it satisfies the metabolic half on its own, so for most people it is the answer to the second question before any blood is drawn. It also feeds the fat estimate.
Triglycerides
A fasting lipid panel value, in mmol/L. It counts twice: inside the fat estimate, where it enters through a logarithm so the order of magnitude is what matters, and as one of the six metabolic markers from 1.7 upwards.
GGT
Gamma-glutamyl transferase, written gamma-GT on Swiss reports. It rises with fat in the liver and with alcohol, which is one reason it is in the fat estimate and not in the metabolic checklist. It enters through a logarithm too.
Type 2 diabetes
A diagnosis satisfies the metabolic half at any weight, including a normal BMI. Nothing is preselected here for that reason: a defaulted no would send a lean reader with diabetes down the third route, which asks for two markers it does not need.
What a scan has shown
If an ultrasound, a FibroScan or an MRI has already found fat in your liver, or ruled it out, that answer replaces the estimate. Imaging beats a blood-based score in both directions, and a calculator that overrode your own scan would be worse than no calculator.
MAFLD, NAFLD, MASLD: which name is current
Three names for overlapping things, and the confusion is genuine. NAFLD came first and is the one most reports still print. MAFLD was proposed in 2020 to replace it with positive criteria. MASLD, metabolic dysfunction associated steatotic liver disease, arrived in 2023 from a second, larger consensus, and is the name the major liver societies have now adopted.
MASLD and MAFLD are close but not the same. Both require fat plus metabolic dysfunction. MASLD needs only one of five cardiometabolic criteria and no separate route for lean patients, and it adds a category for people who also drink significantly. MAFLD is stricter about lean patients, asking for two markers rather than one, and simply does not ask about alcohol.
This page implements MAFLD, the 2020 criteria, because that is what the term means and it is what people search for. In practice the two definitions agree about most people, and where they disagree the difference is usually a lean patient with exactly one metabolic marker. If your report says NAFLD or MASLD, the checklist here is still the right shape of question to be asking.
Who the checklist applies to
MAFLD was written to be applied broadly, which is much of the point of it: it does not need alcohol excluded first, and it does not need a biopsy. What it does need is an adult, and a set of values measured at their usual level.
It applies if
- You are an adult and you want to know whether the fatty liver label fits, or whether one you already have was applied on the current criteria
- You have a recent waist measurement, a recent triglyceride value and a recent GGT, or you can get all three from one check-up
- You have metabolic risk factors, such as a raised BMI, type 2 diabetes, high blood pressure or a raised waist
It does not apply if
- You are under 18, or pregnant: the thresholds are adult ones and pregnancy moves most of them
- Your GGT or triglycerides are raised by something acute, such as an infection, a recent heavy drinking episode or a new medication
- You already have a diagnosis of cirrhosis or another named liver disease: the question the checklist asks has been overtaken
- You are of Asian ancestry: the definition uses lower BMI and waist thresholds there, 23 and 90 or 80 cm, and this calculator implements the higher set only
The checklist is also silent about severity, which is the thing that actually matters. Meeting the criteria says the label fits. It says nothing about how much fat there is, whether the liver is inflamed, or whether it is scarred, and scarring is what decides the outlook. That is a separate question and a separate test.
The units, the way Swiss labs report them
GGT goes in as units per litre, which is what every Swiss laboratory reports. Your report may name it gamma-GT, GGT or gamma-glutamyl transferase. They are the same enzyme under all three names.
Triglycerides are where a mix-up is easy. Swiss reports use mmol/L, so a normal fasting result reads as under 1.7. The same value in the American convention is under 150 mg/dL. Enter 1.8, not 159: triglycerides raise the fat estimate, so a value in the hundreds would push almost anybody past 60 and print fat likely over a clean liver. This calculator refuses the figure instead.
One check-up, one tape measure
Your height, weight and diabetes status you already have. The triglycerides come from a lipid panel and the GGT from a liver panel, both standard on a comprehensive check-up. The waist you measure yourself, and it is the one value on this page no laboratory will give you.
The limits
What this calculator cannot tell you
A definition met is not a disease measured. Four things this page cannot do, in the order they matter.
It says nothing about scarring
This is the important one. MAFLD is common, and in most people it stays harmless. What changes the outlook is fibrosis, and the criteria here do not look for it at all. A met verdict is a reason to ask about a fibrosis assessment, not an answer to it.
The fat half is an estimate, unless you have been scanned
The Fatty Liver Index is good at ruling fat out and only fair at ruling it in, and roughly one person in five lands between its two cut-offs, where it settles nothing. An ultrasound answers the same question properly and costs very little.
Unticked markers count as absent
Four of the six metabolic markers are ones you tick, and an unticked box is read as does not apply. The seventh marker in the published definition, HOMA-IR, is left out entirely, and the triglyceride marker is read from your value without the treatment clause the definition includes. All three gaps run the same way: they can only make a lean reader look like they do not meet the criteria when they do.
The thresholds are the Caucasian set
The definition publishes lower BMI and waist thresholds for Asian populations: 23 rather than 25, and 90 cm for men and 80 for women rather than 102 and 88. This calculator implements the higher set, which is the one that applies to most people in Switzerland and understates the criteria for everyone else.
One checklist, or the trend
A definition is a snapshot. Repeat panels show the direction.
An Ahead Health membership is a year of structured prevention: repeat blood panels covering liver enzymes, lipids, glucose and inflammation, a personal report you can actually read, and a prevention team that goes through it with you. It answers the question this checklist raises but cannot settle, which is where your own numbers are heading.
A membership is prevention, not treatment. It does not replace care from your own doctor.
- Up to four blood check-ups a year, 80 plus biomarkers each
- GGT, ALT, AST and triglycerides tracked over time, not measured once
- HDL, HbA1c and hs-CRP, three of the markers this checklist asks you to tick
- A personal report and an action plan reviewed by Swiss physicians
- A prevention team you can ask about your result
Frequently asked questions
Other calculators
Free tools that ask a different question about the same body.
- BMI calculatorYour weight in relation to your height, and the range that counts as healthy at that height.
- BMR calculatorThe calories your body burns at rest, and the daily total once your activity is added on top.
- SCORE2 calculatorYour 10-year risk of a heart attack or stroke, on the European Society of Cardiology model calibrated for Switzerland.
- FIB-4 calculatorHow likely advanced liver scarring is, from your age, two liver enzymes and your platelet count.
- sMAF-5 calculatorYour risk of liver fibrosis, from your BMI, sex, diabetes status, one liver enzyme and your platelet count. No waist measurement needed.
Sources
The criteria are from Eslam M, Newsome PN, Sarin SK and colleagues, A new definition for metabolic dysfunction-associated fatty liver disease, an international expert consensus statement, Journal of Hepatology 2020, volume 73, pages 202 to 209. The fat estimate is the Fatty Liver Index from Bedogni G, Bellentani S, Miglioli L and colleagues, The Fatty Liver Index, a simple and accurate predictor of hepatic steatosis in the general population, BMC Gastroenterology 2006, volume 6, article 33. The 2023 renaming discussed on this page is Rinella ME, Lazarus JV, Ratziu V and colleagues, A multisociety Delphi consensus statement on new fatty liver disease nomenclature, Journal of Hepatology 2023, volume 79, pages 1542 to 1556.
This calculator provides general health information and is not a medical diagnosis. It does not replace an assessment by a doctor. If your result worries you, or if you have symptoms, speak to a physician.