Land value calculator: what is your site worth to a developer?
Work out the residual land value of a development site: what the finished scheme is worth, less the cost of building it and the developer's profit.
For developers testing a purchase and landowners checking an offer. Every line of the sum is shown.
Free calculator
Your site's residual land value
Based on our 2026 London rates. Enter the number of homes or the GDV, then change any figure to match your scheme.
Want a builder's number, not an estimate?
Send us the address. The team that would build the scheme prices it and tells you what the site is worth.
Buying? See development land and site sourcing. Own the land? See selling land to a developer.
How the residual method works
01
GDV
What the finished homes or space will sell for: homes times the average price, or your agent's total.
02
Build cost
Total floor area times a build rate per m², plus any abnormal costs the site carries.
03
Fees and finance
Design, planning and professional fees, then interest on the money borrowed to build.
04
Planning money
Section 106 and CIL, set by the council for the scheme you plan.
05
Profit, then land
Take the developer's profit off GDV. What is left is what the land is worth to that scheme.
Sites where the numbers decided the deal
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Land value: your questions
How is land value calculated?
Developers usually use the residual method: gross development value, less build costs, fees, finance, planning obligations and their profit. What is left is the most they can pay for the land. Valuers cross-check it against what similar sites have sold for.
What is residual land value?
What a site is worth to one particular scheme: the value of the finished scheme minus every cost of delivering it, including the developer's profit. Change the scheme and the residual changes. Full explanation in our guide to GDV and residual land value.
How much is my land worth with planning permission?
With consent, the residual is worked out from the approved scheme, so the figure is firmer than for land without it. The conditions, Section 106 and CIL that come with the permission all reduce it. Put the consented scheme into the calculator, then see selling land to a developer.
Why do developers' offers differ?
Because they appraise different schemes, or assume different sales values, build costs, programmes and profit. Small differences in those lines make large differences in the residual land value.
Send us the site address
A director looks at the site, the planning position and the numbers, and comes back with the next step.
