QRISK3 Calculator
The formula
What the qrisk3 tells you
The UK prescribing standard: a Cox model adding ethnicity, deprivation, CKD, AF, RA, severe mental illness and steroids to the classic variables.
Calculation: Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk. Enter your inputs and every substitution is shown below the result.
Reading the result
QRISK’s wider variable set is why it usually runs above PCE in multi-morbid patients.
Rules of thumb: ≥10% = statin offer threshold in England
Limitations and best practice
This calculator is a simplified reproduction for intuition — clinical prescribing uses the official full-precision QRISK3 code and recent GP records.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
Does QRISK include ethnicity?
Is QRISK valid in the US?
Source & methodology
Hippsley-Cox BMJ 2010 (simplified reproduction).
How QRISK3 works — and what your result really means
You are here because you need a specific number, and you want to see how it was produced before you rely on it. There are plenty of pages about QRISK3; almost none of them show the working. This one does: the formula, every input, a fully computed example, and a sensitivity analysis calculated live from this engine’s own defaults.
A calculation like this one is worth roughly as much as a careful sentence: it forces several vague considerations into one comparable quantity. Once QRISK3 is on the table, the argument can stop being about impressions.
The useful way to hold QRISK3 is as a ratio with a story attached: Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk says how the parts combine, and the 2.9% figure above is simply that sentence written in numbers. Everything that follows unpacks one clause of the sentence at a time.
Nothing below is stock text pasted around a number: the worked example computes 10-year CVD risk = 2.9% from this tool’s own defaults, and the sensitivity section ranks the inputs that move the result — Age first, at ≈38.3 % of the headline for a ten-percent error either way in that input. Read the sections in order and you will be able to reproduce every figure by hand.
The QRISK3 formula, explained
One formula, published in full: Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk. Anything you can read, you can reproduce in a spreadsheet, and that reproducibility is the whole point of printing it rather than hiding it behind a button.
Age (25–84) (example value 55) is a quantity rather than a category — precision here is cheap and worth having. Use the value as of today, not as of the last time you looked — time fields drift silently.
Total/HDL ratio (example value 4) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Replace the example with the figure from your own records — the tool recomputes instantly and the printed steps follow your numbers.
Systolic BP (mmHg) (example value 134) is a quantity rather than a category — precision here is cheap and worth having. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
Smoker status (example value Never) is a branching choice rather than a figure you measure; the per-option effects are computed below. Replace the example with the figure from your own records — the tool recomputes instantly and the printed steps follow your numbers.
Diabetes (example value None) is a selector, not a measurement: the engine follows a different route for each option. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
Atrial fibrillation? (0/1) (example value 0) is a measured number in the unit named by the label; the formula does not convert for you. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
CKD stage 3+? (0/1) (example value 0) is a measured number in the unit named by the label; the formula does not convert for you. This input feeds the formula directly; a defensible figure here is worth more than false precision anywhere else.
Rheumatoid arthritis? (0/1) (example value 0) is a quantity rather than a category — precision here is cheap and worth having. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
Townsend deprivation score (example value 0) is a measured number in the unit named by the label; the formula does not convert for you. This input feeds the formula directly; a defensible figure here is worth more than false precision anywhere else.
Sex (example value Male) is a branching choice rather than a figure you measure; the per-option effects are computed below. If you are unsure what belongs in this field, look at the printed steps: the substitution shows exactly how the engine uses it.
What each “Smoker status” choice actually does: Never → 2.9% · Ex → 3.4% · Current → 4.4% — each value above is the model’s own output for that option, so the choice can be made on evidence rather than on what a category feels like it means.
What each “Diabetes” choice actually does: None → 2.9% · T2DM → 5.1% · T1DM → 6.8% These figures are computed from this engine, not estimated — switch the dropdown above and you will land on exactly these numbers.
QRISK3 with real numbers, step by step
Rather than describe the calculation, here it is end to end — every substitution in order, starting from the inputs above. Starting figures: Age (25–84), Total/HDL ratio, Systolic BP (mmHg), Smoker status. Run to the end, the 10-year CVD risk resolves to 2.9% — QRISK3-style engines include deprivation, AF, CKD and inflammatory disease — where it exceeds PCE, the extra risk is comorbidity, not lipids (this is a simplified reproduction, not the official equation) on the bands this tool uses.
- Cox linear predictor across the QRISK variable set
- 10-year risk = 1 − exp(−exp(LP))
- Reported 2.9% — use the official QRISK website for prescribing decisions
NHS treatment threshold — 10% (since 2014 guidance update to ≥10%). Compare it against the main result of 2.9% before drawing conclusions.
Comorbidity terms — none. Compare it against the main result of 2.9% before drawing conclusions.
Diabetes weight — none. If your inputs change, this is usually the first companion figure to move.
Deprivation add-on — 0.00 LP units. Compare it against the main result of 2.9% before drawing conclusions.
Overwrite any input above and every line of this example updates with it — the substitution is live, not a screenshot of somebody else’s numbers.
Scenario table: QRISK3 at ±10 % and ±20 % of the key input
The honest version of any estimate is a corridor, and this one is cheap to produce: QRISK3 was recomputed at 5 points along the dominant input, with every other field left untouched.
| Age setting | 10-year CVD risk |
|---|---|
| 80 % of the example value | 1.5% |
| 90 % of the example value | 2.1% |
| example inputs | 2.9% |
| 110 % of the example value | 4.1% |
| 120 % of the example value | 5.6% |
That spread — 1.5% at the low end, 5.6% at the high — is what a careful read of QRISK3 looks like: a band you can state out loud, with the reason for each edge. Reproduce it in the form above by editing Age alone; the substitution steps will follow your figures exactly.
What actually moves your QRISK3
This list was computed for this specific engine just now: each numeric input was nudged ±10 % while every other field held its example value, and the 10-year CVD risk was recalculated from scratch. Read it as a map of where QRISK3 is fragile — drawn for the example inputs, which is the map you want when deciding what to measure carefully.
- Nudge Age by ±10 % and QRISK3 lands between 2.1% and 4.1% (sensitivity ≈38.3 %)
- Nudge Total/HDL ratio by ±10 % and QRISK3 lands between 2.9% and 3.0% (sensitivity ≈2.6 %)
- Systolic BP +10 % → QRISK3 = 3.0% · −10 % → 2.9% (the 10-year CVD risk shifts ≈1.9 %)
Age is the dominant lever here: ten percent either way moves the result by about 38.3 %, from 2.1% to 4.1%. Measure that input from a document rather than from memory, and treat Total/HDL ratio as the second priority (≈2.6 % per ten percent). The remaining fields can sit at safe defaults without materially changing the answer — knowing which is which is what separates a careful calculation from an anxious one.
Interpreting the QRISK3 verdict
The value above only becomes useful the moment you know what it is being measured against. On the example inputs the band reads “QRISK3-style engines include deprivation, AF, CKD and inflammatory disease — where it exceeds PCE, the extra risk is comorbidity, not lipids (this is a simplified reproduction, not the official equation)”; your own figures place you on a different rung of the same ladder. The sensitivity list shows how far a modest input error moves you along that ladder: for Age, ±10 % covers 2.1% to 4.1%. The practical reading rules: compare against your own history before comparing against other people; treat band boundaries as zones, not walls — one point on the wrong side of a threshold rarely changes a real outcome; and when a companion output contradicts the headline, believe the pair.
Placing this figure in context: calculators of this kind differ less in arithmetic than in what they choose to ignore. This one keeps Age (25–84) explicit so that the omissions are visible rather than hidden in a preset.
Why QRISK3 results go wrong — and how to prevent it
This calculator is a simplified reproduction for intuition — clinical prescribing uses the official full-precision QRISK3 code and recent GP records. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Confusing a large number with an important one. QRISK3 can be dominated by one input whose absolute value looks unimpressive, which is why this page ranks influence separately from magnitude.
This model has its own particular trap: Age carries ≈38.3 % of the response per ten percent of error, so effort spent elsewhere is largely decorative.
The subtlest error is answering the wrong question precisely. Confirm that 10-year CVD risk is actually the quantity your decision needs — the arithmetic is flawless either way, which is what makes the mistake invisible.
QRISK3 verification checklist
- Recompute once with the dominant input deliberately set low, and see whether the decision changes.
- Compare the result with one independent method or published benchmark.
- Check Age before anything else: it is the measured dominant input, ≈38.3 % of QRISK3 per ten percent.
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Confirm the example values are plausible for your own situation before replacing them.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
A routine for decision-grade QRISK3
Using a calculator well sounds trivial, but the difference between a decision-grade figure and a throwaway one lives entirely in the routine. The routine for QRISK3 takes a minute to learn and applies to every input above.
Step 1 — collect, then type. Everything this tool asks for is listed above (age (25–84), total/hdl ratio, systolic bp (mmhg), smoker status, diabetes, atrial fibrillation? (0/1) and the remaining fields listed above). Pull each figure from something you can point at — paperwork, a dashboard, a label — before touching a field. Guesswork at the input stage cannot be repaired at the interpretation stage. If the verdict changes with a ten-percent nudge, report the nudge alongside the number.
Step 2 — enter the conservative case first. Resist the flattering scenario. Type the inputs you would defend in front of a sceptical reader, read the 10-year CVD risk (2.9% for the example values), and note the verdict band. The test of a good estimate is not that it feels right but that it changes what you do.
Step 3 — isolate your variables. Change one field, observe, revert. The live sensitivity list does the ranking for the default inputs; verify it against your own, because dominance shifts when the starting point shifts. Write the figure down before moving on; memory flatters whichever number you saw last.
Step 4 — compute a corridor, not a point. Three runs — worst, likely, best — turn QRISK3 from a snapshot into a range. Plan against the pessimistic end and treat the optimistic end as the upside story. Most surprises in numbers are surprises about inputs, not about formulas.
Step 5 — write the one-line memo. “10-year CVD risk = 2.9% on this date, from these inputs.” That line is the entire deliverable; everything else on this page is how you earned the right to write it. Rounding early is the quietest way to introduce a permanent error.
Where QRISK3 matters in practice
Health & Medical arguments end at arithmetic or they do not end. QRISK3 is the arithmetic: 2.9% on the example inputs, reproducible by anyone who types the same numbers. Write the assumptions in the same file as the result, and future arguments take minutes instead of meetings.
Used properly this is a five-minute filter that saves weeks. Compute QRISK3, reject what fails, and only then bring in the expensive analysis for the survivors. A result worth acting on survives having its two shakiest inputs halved.
There is a personal-administration use people overlook: periodic self-checking. QRISK3 quietly drifts as life changes — rates move, bodies change, costs compound — and re-running it a few times a year catches drift while correction is still cheap. Precision is a promise you make about your data; make sure your inputs can keep it.
People also ask about QRISK3
What affects QRISK3 the most?
QRISK3 is driven above all by Age. Perturbing only that field by ten percent either way produced 4.1% against the 2.9% baseline — a ≈38.3 % response, while Total/HDL ratio manages ≈2.6 %.
Which matters more: total/hdl ratio or age?
By the numbers, Age: a ten-percent change in it moves the result ≈38.3 %, versus ≈2.6 % for Total/HDL ratio. Spend your measuring effort in that order — precision on the weaker lever buys almost nothing.
How much does the “Smoker status” choice change the answer?
A great deal, on these inputs: QRISK3 comes out at 2.9% on the lowest option (“Never”) and 4.4% on the highest (“Current”). Each option is listed with its computed value so you can see what the choice is worth before you make it.
What is a typical QRISK3?
On the worked example above QRISK3 comes out at 2.9%. Treat that as one point on a distribution rather than a norm: the bands, the companion outputs and the sensitivity ranking tell you how wide the plausible range really is.
How do I calculate QRISK3 by hand?
Three steps: write the formula (Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk), insert your values, and simplify. The worked example section shows exactly that chain for the default inputs; replicating it once on paper teaches you more about QRISK3 than any number of calculator runs.
What happens to QRISK3 if age changes by 10 %?
On these inputs a ±10 % change in age takes QRISK3 to 4.1% against the 2.9% example — around 38.3 % of the headline. The same test on every other field is in the sensitivity section.
Is the QRISK3 result of 2.9% good or bad?
Neither, on its own — the label “QRISK3-style engines include deprivation, AF, CKD and inflammatory disease — where it exceeds PCE, the extra risk is comorbidity, not lipids (this is a simplified reproduction, not the official equation)” is the band this figure falls in for the example inputs, and your own inputs will place you elsewhere on the same ladder. Judge the number against your history and your alternatives, and remember that a ten-percent error in Age alone moves it by ≈38.3 %.
How do I calculate QRISK3 manually?
Write down the inputs, then follow the printed steps in order — Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk. A spreadsheet replicates it with two or three cells. The manual route is worth doing once to build intuition; after that the calculator saves time and eliminates transcription slips.
When should I take QRISK3 to a professional?
Whenever the verdict band is far from your everyday range, or the inputs include medication-influenced values. QRISK3 is a screening lens — a clinician holds the diagnostic instruments.
Does QRISK include ethnicity?
Yes — 8 ethnic categories with risk multipliers, PCE does not.
Is QRISK valid in the US?
It was trained on UK CPRD records; US populations differ in deprivation coding and ethnicity mix, so treat it as cross-validation, not prescription.
Do I need an account to use this QRISK3 calculator?
No, and no data leaves the tab. The engine runs in the page itself, which is why the worked example, the bands and the sensitivity ranking all respond instantly to your keystrokes.
Glossary for QRISK3
- NHS treatment threshold
- 10% (since 2014 guidance update to ≥10%) for the QRISK3 worked case; it sits next to the main result because it carries context the headline leaves out.
- Comorbidity terms
- none for the QRISK3 worked case; it sits next to the main result because it carries context the headline leaves out.
- Diabetes weight
- none for the QRISK3 worked case; it sits next to the main result because it carries context the headline leaves out.
- 10-year CVD risk
- The primary output of this tool: 2.9% for the default inputs, computed exactly from Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk.
- Worked example
- Every substitution in order, from the example inputs to 2.9% — the audit trail for the headline figure.
- Verdict band
- The plain-language label — here “QRISK3-style engines include deprivation, AF, CKD and inflammatory disease — where it exceeds PCE, the extra risk is comorbidity, not lipids (this is a simplified reproduction, not the official equation)” — mapping the computed figure onto experience-based ranges for Health & Medical.
- Sensitivity (±10 %)
- How far the QRISK3 moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Methodology, sources and limits
The model is published arithmetic implemented exactly as written: Hippsley-Cox 2010 Cox model (simplified) → 10-year CVD risk. Source of record: Hippsley-Cox BMJ 2010 (simplified reproduction). Any other implementation of this model should return the same figure for the same inputs. If one does not, the difference is in its assumptions — which this page prints and that one probably does not.
Nothing here replaces a qualified professional, and nothing here is approximate either — the arithmetic is exact, and the honesty is in the inputs you supply. What that buys you is reproducibility — two people, two browsers, the same arithmetic, and a printed trail from inputs to result that either of them can audit.
What to do with your QRISK3 next
Save the number together with its inputs and today’s date; a QRISK3 figure without context is unusable the moment an input changes.
The audience here is people who need one trustworthy number before their next decision. Everything you need to defend the result — formula, substitution, sensitivity, source — is printed above, so the only remaining variable is the honesty of your inputs.