First choose tissue T1 and T2 values.
Then select your scanning TR, TE and flip angle. You can also set a field inhomogeneity factor. The calculator uses an estimated value of T2* based upon this and the tissue T2.
The graph shows the signal intensity (max = 1) for both tissues, the contrast and the relative contrast to noise ratio (CNR).
Note: this works best on a computer. It will also work on Android and IOS devices.
If you prefer an app-style interface visit here.
Learn more about gradient echo signal and contrast.
Ernst Angle generator for Gradient Echo
MR Signal and Contrast Calculator