The Kidney Simulator
A living model of the heart and kidneys. Move a dial and watch blood split at the filter in real time — filtrate one way, blood the other, urine into the beaker. Nothing here is your data; it is a teaching model you can push around freely.
Loading the kidney simulator…
Best on a laptop or tablet. On a phone, tap Controls to open the dials.
What you can change
Every slider is a real physiological lever. The point is not to hit a target number — it is to see which numbers move together, and which move apart.
- Heart rate & blood pressure
- The push behind everything downstream. Raise the pressure and watch renal blood flow climb with it.
- Hydration
- How much water the body is holding. Sets how much filtrate gets reabsorbed versus passed as urine.
- Afferent & efferent arterioles
- The vessels into and out of the filter. Squeezing them in opposite directions moves filtration in opposite directions — this is what most blood pressure medications act on.
- Kidney health
- The fraction of nephrons still working. Drag it down and you get the chronic kidney disease story: falling GFR, rising creatinine.
- Autoregulation
- The kidney's own defence, holding GFR steady between roughly 80 and 180 mmHg. Switch it off and the plateau collapses.
What the numbers mean
The strip under the simulation and the traces beside it are the same measurements your nephrologist reads on a lab report — just updating live instead of once every few months.
- GFR
- How much plasma the filters clear each minute.
- eGFR
- The same number in the form your lab report uses to stage CKD.
- Creatinine
- The waste product that builds up when filtration falls behind.
- Filtration fraction
- The share of arriving plasma that actually gets filtered.
- Urine output
- What finally leaves the body — collected in the beaker on screen.
This simulator is a simplified teaching model, not a diagnostic tool. It cannot tell you anything about your own kidney function. For that, see how to read your kidney lab results and talk to your care team.
Related reading
These guides cover the next questions patients usually have after this topic.