Mouse Guard / Opening Calculator

Exact Calculator

Calculate mouse guard needs, maximum opening size (3/8"), and seasonal install/remove timing with ventilation assessment.

Number of Hives

Entrance Width(inches)

Entrance Type

Guard Type

Results

Guards needed

Max opening height

0.375inches

Install by

Before first frost (Sept–Oct)

Remove by

After last frost (Apr–May)

Ventilation

Adequate

Installation Tips

Install before first frost when nighttime temps drop below 50°F (10°C).
Maximum opening: 0.375" (9.5mm) - bees pass, mice cannot.
Ensure guard doesn't block dead bee removal.
Check monthly for debris buildup blocking the entrance.
Metal guards are most durable and mouse-proof.

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Disclaimer: BeeCalc Hub calculators provide estimates and guidance based on common beekeeping practices. Results should be adapted to your local conditions, climate, and hive setup. Always consult experienced beekeepers or extension services for critical management decisions. Read full disclaimer →