Lay out boards, posts and spacing

Decks & fences calculators

Deck and fence calculators convert overall dimensions into a preliminary material takeoff. Board width, spacing, run direction and stock length affect deck counts; fence length, panel width, corner locations and gate openings affect posts and panels. The results help compare materials and build a shopping list, but footing size, post depth, railing design, spans and structural connections must follow local codes and manufacturer requirements.

10 working calculatorsUS customary unitsReviewed August 3, 2026

Choose the calculation you need

Start with the material or decision in front of you.

Each tool performs a different takeoff or conversion. Open the closest match, enter real measurements, then review the stated assumptions before using the result to buy material.

deck cost calculator

Deck Cost

Calculate deck square footage and a transparent planning budget from local decking, framing, railing, labor, and contingency rates.

Open calculator deck board calculator

Deck Boards

Estimate deck-board rows, fixed-length pieces, purchased boards, and surface coverage from board width, gap, span, and waste.

Open calculator fence material calculator

Fence Materials

Estimate a complete fence-material takeoff—sections, posts, rails, and pickets—from run length, gates, spacing, dimensions, and waste.

Open calculator fence post spacing calculator

Post Spacing

Calculate fence-post count and actual section spacing for equal runs, with a supplemental concrete estimate from entered hole dimensions and yield.

Open calculator deck stain calculator

Deck Stain

Estimate deck stain gallons and containers from deck dimensions, extra rail or stair area, coated sides, coats, label coverage, and waste.

Open calculator deck joist span calculator

Deck Joist Span

Check a measured deck joist clear span against an approved span-table limit and estimate joist layout quantity from deck width and spacing.

Open calculator deck post spacing calculator

Deck Post Spacing

Lay out equally spaced deck posts along one beam from its length, approved maximum post spacing, approved end overhangs, and extra posts.

Open calculator deck footing calculator

Deck Footings

Estimate concrete volume, cubic yards, packaged-mix bags, and optional bag cost for approved round deck pier shafts and footing bases.

Open calculator fence cost calculator

Fence Cost

Estimate a fence budget from project length and your local material, post, hardware, gate, labor, site-work, and permit quotes.

Open calculator baluster spacing calculator

Baluster Spacing

Calculate the minimum balusters and equal clear gap for one or more rail openings using actual opening width, baluster width, and a chosen gap limit.

Open calculator

How should you use a project calculator?

Begin with finished dimensions from the actual project area, not a plan that may have changed. Break irregular spaces into simple rectangles, triangles or individual runs and calculate each one separately. Keep units consistent, and measure openings, transitions and obstructions that materially change quantity.

The calculator result is a planning takeoff. Suppliers may sell only whole bags, boxes, panels or stock lengths, so purchase quantities are rounded up. Product-specific coverage, local codes, installation methods and site conditions remain the final authority.

Why does the waste allowance matter?

Waste covers cuts, breakage, unusable offcuts, settlement and measurement variation. A simple rectangular project may need only 5% extra, while diagonal layouts, complex roofs, patterned tile and many corners can require 10–15% or more. The right allowance depends on the material and layout, not a universal rule.

Keep unopened returnable packages separate when a retailer permits returns. For batch-sensitive finishes such as tile, flooring or brick, retaining a small matching surplus can also make future repairs easier.