GDV Calculator
Estimate development profit and viability for any residential scheme. Enter land cost, build costs, and unit values to get gross development value, profit on GDV, and return on cost.
Development Revenue
Development Costs
Typical new-build residential: £180–£250/sqft. Assumes 800 sqft avg per unit.
Architects, planning, QS, legal, marketing — typically 8–12% of build cost.
Development finance, bridging — typically 6–8% of total project cost.
Our API returns price trends, comparables, and sold prices by outcode — everything you need to validate your GDV assumptions.
Get free API access →How to calculate development viability
What is GDV?
Gross Development Value (GDV) is the total market value of the completed development — the sum of all units at their anticipated sale prices. It is the revenue ceiling of any project and the basis for all feasibility calculations.
The standard viability formula
Profit on GDV = Profit ÷ GDV × 100
Profit on Cost = Profit ÷ Total Cost × 100
Industry benchmarks
Typical cost percentages
- Land: 15–30% of GDV (varies significantly by location)
- Build cost: £180–£250/sqft for standard residential new-build
- Professional fees: 8–12% of build cost (architects, planning, QS, legal)
- Finance: 6–8% of total project costs (development finance)
- Contingency: 5–10% of build cost
What is gross development value?
Gross development value (GDV) is the total sale value of a completed development scheme — every unit sold at its expected market price, summed together. It is the top line of any residential development appraisal. GDV is not the same as profit: from it you must deduct land, build, fees, finance, and contingency to arrive at development profit.
Why GDV matters for land valuation
Residual land value — the most you should pay for a site — is derived directly from GDV. The standard residual method is: residual land value = GDV − (build + fees + finance + contingency + required profit). If you need 20% profit on GDV, you work backwards from GDV to find the maximum land bid. This is why getting GDV assumptions right is critical before making an offer on a site.
GDV assumptions should be validated against actual transacted prices, not asking prices. Recent sold comparables within a radius of the proposed site give a far more reliable GDV ceiling than advertised prices.
GDV calculator FAQ
What is gross development value (GDV)?
GDV is the total market value of the completed development — the sum of all units at their anticipated sale prices. It is the revenue ceiling of any project.
What is a good profit on GDV?
The industry minimum for residential development is 20% profit on GDV. Below 15% is generally considered unviable. Most developers target 20–25%.
What is profit on cost?
Profit on cost = development profit ÷ total development cost × 100. Industry minimum is typically 25%. It measures return relative to money spent, not total value.
What is a typical build cost per sqft in the UK?
Standard residential new-build: £180–£250/sqft in 2026. High-spec or London schemes can reach £300–£400/sqft. Conversions vary widely.
How do professional fees fit into a GDV appraisal?
Professional fees (architects, planning, engineers, QS, legal, marketing) typically run 8–12% of build cost. Model them separately from contingency (5–10% of build cost).
How can I find comparable sale prices to validate my GDV?
The Homedata API returns recent sold prices within a radius of any UPRN or outcode, filtered by property type and bedrooms. Free tier: 100 calls/month.
Last reviewed: May 2026
Sources: RICS — Financial Viability in Planning · BCIS Building Cost Information Service
Integrate into your own product
Free to startThe comparables endpoint returns recent sold prices within a configurable radius of any UPRN or outcode — filtered by property type and bedroom count — as structured JSON including sale price, floor area (sqm), price per sqm, sale date, EPC rating, and distance, enabling developers to validate GDV ceiling assumptions against actual transacted prices.
Structured as JSON · queryable by UPRN or postcode · ready to embed in any application
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Real values — distances, concentrations, counts — not rounded ratings
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