Fast Beam F3 targeting, ready at the chairside.

TMS Measurement App calculates F3 placement from three head measurements, stores client records locally, and keeps your clinical workflow consistent.

Enter tragus-to-tragus, nasion-to-inion, and head circumference to get X and adjusted Y distances with a clear explanation.

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Offline-first history

Beam F3 formula built-in

Clinician-friendly UI

Instant validation

Treatment session log

Mark the Beam F3 distances

Enter the three head measurements first. Then use the calculated distances to mark the site. The images below show the X, Y, and Z distances as labeled in the Beam F3 guide.

1 X distance from midline

X distance marked from the midline across the forehead

Mark the X cm distance from the midline across the forehead.

2 Y distance along the midline

Y distance marked along the midline on top of the head

Measure the Y cm distance along the midline on the top of the head.

3 Z distance toward the ear

Z distance marked from the vertex toward the ear

Measure the Z cm distance from the vertex toward the ear.

Locate F3

The app calculates X and Y from your measurements and applies the Beam F3 adjustment. Use the steps below to mark the site.

X = 0.1154 × HC | Y = 0.2637 × ((TTT + NI) / 2) | Yadj = Y + 0.35 cm

Measure X along the circumference from the midline toward the left side.
From the vertex (Cz), draw a line through the left pre-auricular point.
Measure Yadj along that line to locate the F3 point.

Reference map

The EEG reference map helps confirm the F3 region relative to the 10-20 system. Use it alongside the calculated distances for placement.

The app stores every measurement locally, so clinicians can review previous sessions without network access.

Track treatment sessions

Record each TMS session under its measurement: stimulation intensity, pulses, frequency, and more. Every session is saved locally on the device, so you can review a client's full treatment history offline.

Intensity (% motor threshold) and the motor-threshold baseline (% MSO)
Total pulses, frequency (Hz), and the train breakdown (trains, pulses per train, durations)
Session date, stimulation site, and free-text notes — editable any time

Calculate F3

Enter the three head measurements in centimeters to calculate the Beam F3 distances used for site marking.

X (circumference) —

Y (radial distance) —

Yadj (adjusted) —

X = 0.1154 × HC, Y = 0.2637 × ((TTT + NI) / 2), Yadj = Y + 0.35 cm.