Skip to content

Gutter Bracket Calculator — Brackets, Fittings & Guttering

Calculate gutter brackets, fittings and guttering lengths for your roof. Includes outlets, corners and union joints.

Total length of all gutter runs

One per downpipe

Internal and external corners

How We Calculate This

This calculator divides the total gutter run by the bracket spacing to determine bracket quantities, and by gutter length to determine how many lengths you need. Fittings are calculated based on the number of outlets, corners and joints.

The formula

Brackets = (Total run ÷ Spacing) + 1
Gutter lengths = Total run ÷ Length per piece
Union joints = Gutter lengths - 1

Frequently Asked Questions

Last updated: March 2026

All calculations are estimates. Verify with your supplier.