MRISim

Welcome to MRISim

The real MRI physics engine, running in your browser.

New to MRI? Open Lessons and start the “Start here” track — short reading-first walkthroughs. Or tick Label the anatomy to name the structures and hover any pixel to see which tissue it is and its T1/T2/PD.
Sequence & timing — pick a sequence and sweep TR / TE / flip on the left panel. Each value is editable — type an exact number (or arrow-key it) instead of dragging. Section headers collapse, and the Find a control box at the top jumps you to any parameter.
Navigate — scroll the wheel or press ↑/↓ over the image to change slice; drag the image to window/level (R resets); hover the image to read the tissue and its T1/T2/PD under the cursor. On a touchscreen: drag with one finger to window/level, and use the Slice slider to scroll slices.
Compare — “Set as A”, then tweak B to see the difference side by side.
FOV planning — toggle the 3-plane localizer (F). The prescription shows as a band of the slice's true thickness — or a stack of slices with a gap, or the whole 3-D slab. Click a cross panel to move the slice, drag the slice band to angle the plane (oblique), and drag the dashed FOV box to resize or recentre it. Double-click to reset. More slices with no gap cost SNR (slice cross-talk).
Protocol planning — the scanner-console workflow (top-bar button): pick an exam, then prescribe each sequence on the scout images and acquire it, one after another, like a real console. Reports scan time + SNR, and you can drag/window-level/re-run the acquired series.
Contrast map — toggle the TR×TE map to see the whole contrast landscape for a tissue pair (bright = high contrast), with your current protocol marked — so you can see where contrast comes from, not just one curve.
Show the math — toggle it on, then hover a pixel to see the active sequence's signal equation with that tissue's T1/T2/PD and your TR/TE plugged in, and the resulting signal — the number that becomes the pixel.

This browser edition is a convenience subset. For the fullest, most robust experience — real body atlases, NIfTI/DICOM, the complete planning workflow and faster rendering — grab the desktop app.

Welcome to MRISim

Guided lessons

Learn MRI from scratch

Protocol

Anatomy & Sequence

Visualizations

Timing

Contrast & effects

Artifacts (teaching)

Acquisition

Measure

3D acquisition & reconstruction

Parallel imaging & sampling

Measurements

Resolution	—
Scan time	—
SNR (WM / GM)	—
CNR (WM–GM)	—
SAR (head)	—