handyfig
USUKAU

Fence Panel and Post Calculator

Work out how many fence panels, posts and rails a straight fence needs, with gates taken out of the run.

Length of fencePanel widthGate width
Key One more post than panels. Gates count towards the length.
Units
m
Typical panel. The standard pre-made panel is 6 ft (1.83 m) wide, in heights of 3, 4, 5 and 6 ft. Source: Jacksons Fencing, listed below.
m
Typical gate. A single garden gate is often about 0.9 to 1 m wide. Editorial rule of thumb.
m
Panels7 panels
Posts8

Run 12 m = 12 m; ÷ 1.83 m panels = 6.56, rounded up to 7. Posts: 7 panels + 1 = 8.

Corners, slopes and heavier gate posts are not included.

Fig. 1 Panels and posts for your fence.

Work out the concrete for 8 posts

Every formula is tested against worked examples. How we check

Panel widthPanelsPosts
1.5 m89
1.8 m78
1.83 m78
2.4 m56

Fig. 2 The same fence with different panel widths.

Last checked 10/11/2026. Sources: LSBUD: Linesearch Before U Dig (UK); Jacksons Fencing: Fence panel heights and widths (6 ft, 1.83 m wide is the standard width).

Guide

How the amount is worked out

Panels = (fence run − gate widths) ÷ panel width, rounded up. A straight run needs one more post than it has sections, and each gate adds a section: posts = panels + gates + 1. Rails = panels × rails per panel, for fences built from rails and boards.

Example. 12 m of fence with 1.8 m panels is 6.67, so 7 panels and 8 posts.

Concrete for the posts

Each post sits in a hole, and the hole’s volume sets the concrete you need. Use the concrete calculator with the post hole shape, or follow the button below the result to carry the post count across.

Common mistakes

  • Counting panels but not posts. A run of 7 panels has 8 posts.
  • Forgetting that gates need stronger posts and hardware.
  • Ignoring corners and slopes. Corners add posts, and a sloping run needs stepped or racked panels, which this tool does not model.

Safety and rules

Before you dig, check for buried pipes and cables, for example with the free LSBUD service, and check local rules and any permissions that apply to your property. Fence height limits and boundary rules apply, and you may need permission next to a highway or for listed buildings, so check before you build. This is not building or structural advice.

Common questions

How many fence panels for 12 metres?

With 1.83 m (6 ft) panels, 6.6 rounds up to 7 panels and 8 posts. With 1.8 m panels it is 7 panels as well.

How far apart should fence posts be?

Panel width sets the spacing. Most UK panels are 1.83 m (6 ft) wide, with the posts set slightly more than a panel width apart, centre to centre.

How deep should the holes be?

A common rule of thumb is about a third of the post’s total length in the ground. Check the panel maker’s guidance.

Can I put up a fence of any height?

No. There are height limits without permission, and different rules at the front of a property and next to a road. Check with your local council.

Planning a related job?

Worked examples

More calculators

Paying for the project?