🌿 Biodiversity Net Gain Calculator
DEFRA Metric 4.0 simplified assessment tool. Calculate biodiversity units for habitat baseline and enhancement, verify statutory 10% net gain compliance, and generate requirements checklist for planning applications.
Calculating biodiversity units...
📜 Relevant Legislation
- Environment Act 2021: Mandatory 10% BNG for major developments (Feb 2024) and minor (April 2024)
- NPPF Policy N2: Biodiversity net gain requirement and priority habitats
- DEFRA Biodiversity Metric 4.0: Official calculation methodology
- Local Plan policies: May require higher BNG % or specific habitat types
- Conservation Covenants: Available under Environment Act for long-term habitat protection
- National BNG Register: All BNG schemes must be registered (www.register.biodiversityexchange.org.uk)
About this tool: BNG Calculator
Biodiversity Net Gain assessment using DEFRA Metric 4.0 — habitat units, 10% mandatory gain, statutory credit costs, and exemption checking.
Required for most planning applications since February 2024. Mandatory 10% BNG applies unless your project is exempt (e.g. householder, self-build under thresholds).
Environment Act 2021, DEFRA Metric 4.0
Use these tools early in your project to understand what environmental, heritage, and ecological constraints affect your site. The results will determine which technical reports you need and shape your application strategy.
Guidance to help you prepare — not formal planning advice. Check the current policy text and your council's local plan before relying on it.