Use this virtual-reality calculation for a first-order display, optics, tracking, rendering, or latency estimate when all stages and units are explicitly defined.

Angular Error Degrees (deg)

Required number in deg.

Pixels Per Degree (px/deg)

Required number in px/deg.

The cited overview of Virtual reality sickness supplies background for the terminology and domain context used by this tool.^[1]

Approximate horizontal reprojection error in pixels from signed angular error and nominal pixels per degree. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Error Pixels (px)

Returned number in px.

• Lens calibration, per-eye geometry, display scanout, asynchronous pipelines, tracking filters, workload variation, user anatomy, and device firmware can make measured VR behavior differ from a serial model.
• Pixels Per Degree must be at least 0.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Validate the estimate on the target headset with calibrated motion, optical, frame-timing, and latency measurements under a representative workload.

• Display Pixels Per Degree

  Nominal horizontal panel pixels per optical degree for one eye; ignores lens distortion and usable-pixel losses.

• Resolution From Ppd Fov

  Minimum integer horizontal pixel count for a target nominal pixels-per-degree and horizontal field of view.

• Timewarp Correction Angle

  Approximate angular pose correction from angular velocity times late-update latency.