Australia

Free tools for your septic system

Clear, explained calculators to size your tank, estimate costs and pick the right system — no jargon, nothing to sell.

📏What size septic tank do I need? Sizing calculatorEstimate your septic tank size from the people in the house, following AS/NZS 1547.💵How much does a septic system cost in Australia?Estimate the full cost (tank + excavation + install) by tank type and site.🛢️How often to pump out a septic tank (and the cost)Estimate the pump-out frequency and yearly cost by system type and household.🧭Septic tank or AWTS? Which system suits youAnswer three questions and find which on-site system fits your block.📐Can the trench go there? Check the setbacksBore, dam, waterway, boundary, building, pool, stormwater drain — the distances your council will measure.📏How long does my absorption trench have to be?The AS/NZS 1547 formula, with the real design loading rate for your soil category.