Labs & Simulations
Tools you play with rather than fill in. Where a calculator gives you a number, these let you change something and watch what happens: an arc traced as it flies, a network splitting into subnets, a signal running down a wire, a pan climbing the candy ladder, ten thousand test results sorting themselves into true and false positives. Built on real, cited science, and running entirely in your browser.
A calculator answers a question you already knew how to ask. These let you change one input and watch what happens to everything else — which is how you find the things you did not know to ask about. Every one runs the real equations frame by frame, so the picture and the numbers always agree. More on that below.
Physics
Open the lab →Each one integrates the real equations of motion frame by frame, so the picture and the numbers come from the same maths.
Computing & Electronics
Open the lab →Two tools for the parts of computing that are hard to picture — both show you the bits rather than just the answer.
Probability & Money
Two intuitions that almost everyone gets wrong the first time — what a positive test result is worth, and how much of a long-run balance is growth rather than contributions. Both let you move the inputs and watch the answer change shape.
The Kitchen & Gut Lab
Open the lab →A lab within the lab: four bench reactions and three zones for what happens after you eat.
What a simulation is, and what it is not
A calculator answers a question you already know how to ask. A simulation lets you change an input and watch the consequence, which is a better way to learn something you did not know to ask about. The Food Combination Checker is the clearest example: nobody arrives wondering whether tea blocks iron absorption, but everybody who mixes tea with lentils finds out.
The trade-off is honesty about precision. The Digestion Simulator computes each stage from the food’s fat, fibre and water content, and the direction of every effect is well established — but the exact minute counts are modelled, not measured, and the page says so where you cannot miss it. A simulation that hides its own uncertainty is worse than a table of numbers.
Where the science comes from
Every claim in these tools traces to a named source, listed on the page that makes the claim rather than in one site-wide block: the NIH Office of Dietary Supplements for nutrient absorption, NIDDK for digestive anatomy, Monash University for FODMAPs, and the NHS, NICE and Coeliac UK for the clinical patterns in Gut Check.
Where a rule is traditional rather than demonstrated — the Ayurvedic prohibition on fish with milk, for instance — it is badged as folklore rather than cited to a source that does not support it. Where the evidence is genuinely contested, such as the widely repeated claim that black pepper multiplies turmeric absorption twentyfold, the card says the evidence is split and explains why.
Nothing you enter leaves your browser
These tools ask about food and symptoms, which is more personal than most of what this site does. There is no account, no submission and no server: every reaction, timing and pattern is computed on your own device, and the only thing stored is your Mix Lab discovery count, in your own browser, which you can clear at any time.
Health tools that pair with these
The lab is about what food does on the way through. If you are working on what it adds up to, the health calculators are the numeric side of the same question.