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Fence Panel Calculator — Panels, Posts & Fittings
Calculate how many fence panels, posts, postcrete bags and fittings you need for your boundary fence. Uses standard UK panel sizes.
Total run of fencing — at least one panel width (≈1.8m)
One gravel board per bay — protects panels from ground contact
One cap per post — protects post tops from rain
Adds 10% extra panels for breakages or cutting
10% is standard for panel fencing
Enter your supplier price for a cost estimate
Enter your supplier price for a cost estimate
Enter your supplier price for a cost estimate
Rule of thumb: ⅓ of post height, 600mm minimum for a 6ft fence. Deeper holes need proportionally more postcrete.
Default: 20kg bags
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How We Calculate This
Our fence panel calculator divides your total fence run length by the panel width to determine the number of panels needed. The number of posts is always one more than the number of panels, as each bay requires a post on either side. Building close board fencing from individual featheredge boards instead of pre-made panels? Use our close board fencing calculator to work out how many fence slats you need.
The formula
Panels = Fence length ÷ Panel width (rounded up)
Posts = Panels + 1
Post length = Panel height + 600mm (burial depth)
For example, a 10m fence run with standard 1.83m panels: 10 ÷ 1.83 = 5.46, rounded up to 6 panels. You would need 7 posts, each at least 2.43m long (1.83m panel + 0.6m burial).
The count assumes each bay is spaced at the panel width and that every run starts and ends with its own post (posts = panels + 1) — the standard UK merchant convention. Where a run butts up against a wall or an existing post at one end, subtract one post from the total.
Postcrete quantities
Postcrete (fast-setting post mix) is estimated at 2 bags of 20kg postcrete per standard 100×100mm timber post set in a roughly 200–250mm wide × 600mm deep hole (about 1.5 bags for a lighter 75×75mm post, around 3 bags for a heavier concrete post). The estimate adds one bag for fences 2m or taller. Because a hole’s volume scales with its depth and width, the calculator multiplies the bag count by your chosen burial depth — a 1000mm-deep hole needs about two-thirds more postcrete than the 600mm reference hole, and a wider 300mm hole roughly 3 bags rather than 2. For very loose or sandy soil, allow an extra bag per post. These figures are merchant rules of thumb — always check the bag’s coverage and your actual hole size.
UK panel fencing tips
- Standard UK fence panels are 1.83m (6ft) wide — this is the most common size
- Always use gravel boards to protect panels from ground contact and rot
- Concrete posts last longer than timber but cost more upfront
- Check your boundary line before starting — the posts should be on your side
- In exposed locations, consider using concrete posts for extra wind resistance
Frequently Asked Questions
The standard fence panel in the UK is 1.83m (6ft) wide by 1.83m (6ft) tall. This is the most common size sold at B&Q, Wickes, and builder's merchants. Panels also come in 1.52m (5ft) widths and various heights from 0.9m (3ft) to 1.83m (6ft). Always check with your supplier as sizes can vary slightly between manufacturers.
Fence posts should be buried a minimum of 600mm (2ft) in the ground. This provides adequate stability for panels up to 1.83m (6ft) tall. For exposed or windy sites, consider going deeper to 750mm. The post length should therefore be the panel height plus at least 600mm — so for a 6ft fence, you need 8ft (2.4m) posts.
For a standard 100×100mm timber post in a ~200–250mm wide × 600mm deep hole, allow 2 bags of 20kg postcrete; a lighter 75×75mm post needs about 1.5 bags. Heavier concrete posts (which sit in a wider hole) take around 3 bags. Add an extra bag for fences 2m or taller, and remember a wider or deeper hole needs proportionally more — a 300mm wide hole needs roughly 3 bags rather than 2 because the volume scales with the hole. Postcrete sets in about 5–10 minutes when mixed in the hole with water, making it much faster than standard concrete. For precise volumes, use our Concrete for Fence Posts Calculator.
Gravel boards are not mandatory but are highly recommended. They sit between the ground and the bottom of your fence panels, preventing the panels from rotting through ground contact. Concrete gravel boards are the most durable option and typically last 20+ years. They are especially important on sloping ground or where soil is damp. Use our Gravel Board Calculator for quantities and costs.
In England and Wales, you can erect a fence up to 2 metres (6.5ft) tall without planning permission, provided it does not front a highway (where the limit is 1 metre). However, if your property is listed or in a conservation area, you may need permission regardless of height. Always check with your local council before starting work.
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Last updated: February 2026
Verified against UK standards · estimates only, confirm with your supplier.