Flight Category Calculator
Turn a ceiling and visibility into VFR, MVFR, IFR, or LIFR.
Inputs
Result
Flight category
IFR
Instrument — ceiling 500–1000 ft or vis 1–3 sm
Ceiling
800ft AGL
Visibility
2sm
IFR — ceiling 800 ft, visibility 2 sm
Formula
Ref- LIFR: ceiling < 500 ft or vis < 1 sm
- IFR: ceiling 500–<1000 ft or vis 1–<3 sm
- MVFR: ceiling 1000–3000 ft or vis 3–5 sm
- VFR: ceiling > 3000 ft and vis > 5 sm
Worked example
RefCeiling 800 ft, visibility 2 statute miles.
- 1.Ceiling 800 ft → 500–1,000 ft band → IFR.
- 2.Visibility 2 sm → 1–3 sm band → IFR.
- 3.Take the more restrictive of the two → IFR.
IFR — instrument conditions.
How it works
RefThe VFR/MVFR/IFR/LIFR categories summarise whether conditions allow visual flight, and colour the weather charts pilots scan before departure. The category is the more restrictive of the ceiling-based and visibility-based bands — a high ceiling doesn't help if the visibility is poor.
DGCA student tip
ExamMemorise the four boundaries as a ladder: 500 / 1,000 / 3,000 ft for ceiling and 1 / 3 / 5 sm for visibility. The colours (LIFR magenta, IFR red, MVFR blue, VFR green) are worth knowing for chart questions.
Common mistakes
Watch- Taking the better of ceiling/visibility instead of the more restrictive.
- Using a FEW/SCT layer as the ceiling (only BKN/OVC count).
- Mixing statute miles with nautical miles for visibility.