Area estimator
How much do you buy for a 5 × 4 patio or a 100 m² lawn? Pick a surface, pick a teardown, get litres and grams — then jump into the full calculator.
How much do I buy
Area estimator
Measure the patio or lawn, pick a teardown, and see concentrate, water and batch cost for that surface. Thin wrapper over the same mixing maths as the calculator — always check the SDS.
20 m²
Patio & exterior · 1:4.5 (to ~4.5% working, matching Algon 1:3)
Batch for 20 m²
- Concentrate
- 606 ml
- Water / carrier
- 2.7 L
- Working mix
- 3.3 L
- Batch cost
- £1.21
- vs ~£15.99 branded (92%)
Bulk: Spirit vinegar 25% (acetic acid) · CAS 64-19-7. Indicative maths only — shop packs and coverage vary with porosity and weather.
DupeStack provides chemical concentration data and educational mixing guides only. Wellness pages compare food supplements, not medicines or prescribed treatments. Always review the supplier Safety Data Sheet (SDS) and comply with UK Health and Safety Executive (HSE) and COSHH regulations when handling concentrated substances. Mixing and storage are at your own risk. Some links are affiliate advertisements (Amazon Associates, eBay Partner Network, and Awin when those programmes are live). Commissions do not change listed concentrations or calculator output.