What width webbing should I use?

25mm is the most common for bag straps and dog leads. 38mm suits larger bags and backpacks. 50mm for belts and heavy-duty straps. Match the webbing width to your hardware (buckles, sliders, D-rings).

How much extra do I need for hardware?

Allow 5-10cm per end for looping through hardware (buckles, D-rings, sliders). An adjustable strap needs extra length: the adjustment range plus hardware allowances on both ends.

What type of webbing should I use?

Polypropylene: lightweight, does not absorb water, good for outdoor use. Cotton: soft, comfortable for handles, takes dye well. Nylon: strong, abrasion resistant, good for heavy loads. Polyester: UV resistant, colourfast.

How do I seal the ends of webbing?

Synthetic webbing (polypropylene, nylon): seal cut ends with a flame to prevent fraying. Cotton webbing: fold ends under or cover with a fabric tab. Always seal before sewing.

sewcalcs.uk

Webbing Calculator — Bag Straps & Belts

Calculate webbing length for bag straps, belts and hardware.

Strap TypeSets a typical hardware allowance below — override it if needed

Finished Strap Length

The finished strap length you want, excluding hardware loops

Number of Straps

How many identical straps to cut (e.g. 2 bag handles)

Hardware Allowance

Extra webbing folded through buckles, sliders, D-rings and clips

Webbing Price (optional)

Price per metre of webbing, for a cost estimate

How We Calculate This

Total webbing is the finished strap length plus an allowance for wrapping through hardware at each end, multiplied by the number of straps. Choosing a strap type sets a typical hardware allowance — bag handles fold back onto D-rings (~10cm), an adjustable shoulder or crossbody strap threads a slider and two swivel hooks (~25cm), a belt returns through its buckle (~15cm), and a dog lead needs a handle loop plus a trigger clip (~25cm). You can override the allowance for your exact hardware.

The formula

Per strap = Finished length + Hardware allowance

Total webbing = Per strap × Number of straps

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before cutting or purchasing fabric.