Land Offset Estimator

Import GeoJSON

Start: search a location, then click Draw area and click around the site boundary.

Screening tool

Offsets for an area of land

Draw a site to estimate the biodiversity offset it would trigger if cleared, or the credits it could generate as an offset site, plus carbon lost from clearing or gained from revegetation.

Area

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No area drawn

Jurisdiction

Draw an area to detect

Mean annual rainfall

Auto-filled from ERA5 (2016–2025)

Centroid

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Methods & sources

How the numbers are worked out

This is a screening estimate for early planning and budgeting. It does not replace an accredited assessment, the regulator's own calculator, or a site survey. Every input marked as an assumption should be replaced with site data before you rely on the result.

Victoria

General habitat units = extent × condition score × general landscape factor × 1.5, where the general landscape factor = 0.5 + (strategic biodiversity value score ÷ 2). Species habitat units use the habitat importance score and a multiplier of 2. Minimum SBV of the offset is 80% of the weighted average SBV removed. (Guidelines for the removal, destruction or lopping of native vegetation, 2017; as applied in DEECA Native Vegetation Removal reports.)
Offset site units = area × gain score per hectare × general landscape factor. Gain scores come from the Native Vegetation Gain Scoring Manual and depend on condition, security and management commitments; the default here is an assumption.
Credit prices are set by sellers on the Native Vegetation Credit Register and vary widely by catchment and attributes. Use a broker quote.

New South Wales

Ecosystem credits = change in vegetation integrity (VI) score × area × biodiversity risk weighting × 0.25 (BAM 2020, Equation 1). Credits created at a stewardship site use the predicted VI gain × area × 0.25. The BAM Calculator (BAM-C) also handles species credits, hollow-bearing trees, VI thresholds, security benefit and gain risk-weighting, which are not modelled here.

Queensland

Financial settlement = (offset area × on-ground cost per ha) + landholder incentive payment + administrative cost (25% of on-ground cost, floor $50,000 for impacts over 2.5 ha, cap $1,000,000). Offset area = impact area × matter multiplier (maximum 4). The terrestrial sliding scale applies to offsets over 100 ha; the landholder incentive payment has a $10,000 floor. (Queensland Environmental Offsets Policy v1.15, Appendix 4.) On-ground cost and land value come from the policy's subregion and LGA tables or the DETSI online calculator. The framework is under review in 2026.

South Australia

Total biodiversity score = unit biodiversity score (vegetation condition × landscape context × conservation significance) × area, from the Bushland or Rangeland Assessment Method. The Native Vegetation Council sets the SEB points and the payment rate per point into the Native Vegetation Fund.

WA, Tasmania, NT, ACT, EPBC Act and New Zealand

These have no single state formula a desktop tool can reproduce, so a transparent quality-hectare method is used: impact = area × habitat quality (0–10); offset gain per hectare = (quality with management − current quality) × confidence of success. This follows the logic of the former EPBC Offsets Assessment Guide without its time-discounting and averted-loss terms.
EPBC Act: the National Environmental Standard for Environmental Offsets was made on 19 August 2026 and requires a net gain; proponents can deliver an offset or pay a restoration contribution charge. The draft method for calculating that charge closed for comment on 14 October 2026 and is not modelled here.
New Zealand: the Planning Bill and Natural Environment Bill passed their third readings in September 2026, replacing the RMA in stages to 2030 while existing plans and consents continue. Biodiversity offsetting currently follows the NPS-IB offsetting principles (net gain required); use the net-gain margin to reflect that.

Land carbon

Australia, revegetation: indicative 25-year average sequestration for mixed-species environmental plantings by rainfall band (about 1 t CO₂-e/ha/yr below 350 mm rising to about 6.5 above 800 mm), drawn from FullCAM-based studies (CSIRO, MLA, Henry et al. 2015). Narrow belts (<40 m) sequester more per hectare. ACCU estimates deduct the 5% risk-of-reversal buffer, plus a 20% reduction for a 25-year permanence period. Rainfall is the 2016–2025 ERA5 mean from Open-Meteo, which is coarse; override it with a local BoM figure. For a real project, model the site in FullCAM.
New Zealand, afforestation: NZUs under averaging accounting use the ETS standard carbon tables (forests under 100 ha): radiata pine about 20.1 t CO₂/ha/yr to age 16, exotic hardwoods about 26.7 t to age 12, indigenous forest about 8.4 t to age 23 (Scion, 2023). Radiata tables vary by region; this uses the national average.
Clearing emissions: live biomass carbon (t C/ha) × area × share removed × 44/12. Australian presets are national averages from the Australian Greenhouse Office's 2003 biomass totals divided by forest area by type (ABS Year Book 2004); NZ presets use the IPCC 2006 default above-ground stock for NZ temperate oceanic forest (360 t dry matter/ha) and the ETS indigenous table. Soil carbon is excluded. Site biomass varies several-fold from these averages.
Prices (editable): ACCU spot A$37.75 (CORE Markets, close 19 Oct 2026); NZU spot NZ$49.50 (Marex via PF Olsen, 19 Oct 2026).

Map data

Imagery © Esri and contributors; street map © OpenStreetMap contributors; place search and jurisdiction lookup via Nominatim; rainfall via Open-Meteo (ERA5). Areas are geodesic (Turf.js). Overlapping polygons are counted twice.