PartyCalcs.uk
Bunting Calculator — Metres of Bunting Needed
Work out how many metres of bunting to buy for your party venue or outdoor space.
Extra for tying, overlap, and wastage
How We Calculate This
This calculator estimates bunting length based on your wall measurements and hanging style.
The formula
Total bunting = wall length × number of walls × style multiplier + tying allowance + extra
Straight runs add 10% for tying and overlap. A draped or swag style adds about 20% more for the dip in each loop (a deep swag can need more). Criss-cross overhead roughly doubles the straight distance — an estimate based on running diagonals across a typical rectangular room, where two diagonals are close to twice a single wall run. A tying allowance (default 0.3m at each end) is added per run, and an optional 10% is included for wastage and trimming.
The estimated flag count divides the total length by your flag pitch — the flag width plus the gap between flags (default 30cm, which gives about 3.3 flags per metre, matching typical UK shop-bought bunting).
Frequently Asked Questions
Measure the walls you want to decorate in metres. For straight runs, add about 10% extra for tying and overlap. For a gentle draped or swag effect, add roughly 15-20% more than the wall length to allow for the dip in each loop. A deep, pronounced swag can need more.
Most UK bunting is sold in lengths of 3m, 5m, or 10m. Fabric bunting tends to come in longer lengths. Check the listing carefully as some cheaper options are shorter than expected.
Typical UK shop-bought bunting fits about 3 to 3.5 flags per metre — for example, cotton bunting has around 33 triangular flags on a 10m string (a 19cm flag plus a 10cm gap, about a 29cm pitch). So a 3m string holds roughly 10-12 flags. The flag count this calculator gives uses your flag pitch (flag width plus the gap between flags).
Absolutely. For DIY bunting, each flag triangle typically uses a 20cm x 20cm piece of fabric, with a gap of about 10cm between flags. That gives a pitch (flag plus gap) of around 28-30cm, so a 3m string fits about 10-12 flags.
Use cable ties, garden twine, or adhesive hooks. For outdoor events, secure bunting firmly as wind can pull it down. Nylon or plastic bunting withstands weather better than paper or fabric.
Related Calculators
Fairy Light Calculator
Calculate how many metres of fairy lights you need to decorate your party venue, marquee or garden for a magical celebration. Free calculator.
Streamer Calculator
Estimate how many rolls of streamers and crepe paper you need to decorate your party venue or celebration space. Free online calculator.
Banner Calculator
Work out the right banner sizes and quantities to decorate your party venue, including happy birthday and custom message banners. Free calculator.
Balloon Calculator
Calculate how many balloons you need for your party venue, including latex, foil and helium options for any celebration. Free online calculator.
Confetti Calculator
Calculate how much confetti you need for your celebration, wedding send-off or party table scatter based on guest numbers. Free calculator.
Was this calculator helpful?
Last updated: February 2026
All calculations are estimates. Adjust quantities based on your guests and event type.