Bee Frame Spacing Calculator
Calculate optimal frame spacing in your beehive based on frame count, box width, and bee space requirements.
Understanding bee space and frame spacing:
Bee space is the fundamental principle of modern beekeeping, discovered by Reverend Lorenzo Langstroth in 1851. Bees leave passages of 6–9 mm (¼–⅜ inch) open for travel. Spaces smaller than 6 mm get sealed with propolis. Spaces larger than 9 mm get filled with burr comb. Correct frame spacing keeps your hive manageable and your bees productive.
Frame spacing formula:
Center-to-center spacing = (Box internal width - Frame end-bar width) ÷ (Number of frames - 1)
Gap between frames = Center-to-center spacing - Top bar width
For standard Langstroth equipment:
- Top bar width: 35 mm (1⅜ inches)
- End bar width: varies by frame type
- Ideal bee space gap: 6–9 mm
Standard spacing by hive type:
| Hive Type | Box Width (mm) | Frames | Center-to-Center | Gap |
|---|---|---|---|---|
| Langstroth 10-frame | 465 mm | 10 | 35 mm | 9.5 mm |
| Langstroth 8-frame | 370 mm | 8 | 35 mm | 9.5 mm |
| National (UK) | 460 mm | 11 | 35 mm | 8.0 mm |
| Dadant | 505 mm | 11 | 38 mm | 10.0 mm |
| Top-bar hive | varies | varies | 35 mm | 3–6 mm |
Example calculation:
For a 10-frame Langstroth brood box:
- Internal width: 465 mm
- Number of frames: 10
- End-bar width per frame: 35 mm
- Total frame width: 10 × 35 = 350 mm
- Remaining space: 465 - 350 = 115 mm
- Side gaps (2): 115 ÷ 11 spaces = 10.45 mm per gap
- Center-to-center: 35 + 10.45 = 45.45 mm
When to modify spacing:
Honey supers often use wider spacing (9 frames in a 10-frame box) to encourage bees to draw comb deeper, making uncapping easier. This gives 38 mm gaps — bees fill the extra space with deeper comb cells.
Brood boxes should always use standard tight spacing. Wide spacing in brood areas causes bees to build double-thickness comb or bridge comb between frames, making inspections difficult.
Castellated spacers lock frames at fixed intervals and are ideal for honey supers where you want consistent wider spacing without manual adjustment.