What is a good UDS percentage for a flat?

It depends on project density. As a rule of thumb, low-rise apartments typically give UDS of 40-50% of flat area, mid-rise 25-35%, and high-rise towers 15-25%. The more important check is whether the stated UDS matches the proportional fair share.

Where is UDS mentioned in property documents?

UDS is stated in the sale deed, usually in the schedule of property, and it is what actually gets registered in the buyer's name. It should be cross-checked before registration.

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UDS Calculator — Is Your Undivided Share Fair?

Q: What is UDS (Undivided Share of Land)?

When buying a flat, the buyer owns an undivided share of the total plot proportional to the flat's area, rather than a separate piece of land. The building depreciates over time, but the UDS holds and grows in value and determines compensation in redevelopment.

Q: Why does UDS matter for redevelopment and resale?

In redevelopment, compensation and negotiating power are based on UDS rather than flat size. In resale of older buildings, the land component increasingly drives value, so two identical flats with different UDS can have very different real values.

Your flat comes with a share of the land it stands on. Calculate your fair UDS, verify what the builder has stated in the sale deed, and estimate your land value.

Total Land Extent of the Project

Found on the project approval / sale deed schedule.

Total Saleable Built-up Area of All Flats (sq.ft)

Ask the builder, or approximate: average flat size × number of flats.

Your Flat’s Super Built-up Area (sq.ft)

Building Type

Optional Checks

UDS Stated in Your Sale Deed (optional)

Guideline Value of the Land (₹ per sq.ft) (optional)

Check your survey number on the TNREGINET portal.

🏠 Enter your project details to see your fair share of the land — and whether the builder’s stated UDS matches it.

Frequently Asked Questions

What is UDS (Undivided Share of Land)?

When you buy a flat, you don’t own the land separately — you own an undivided share of the total plot, proportional to your flat’s area. The building depreciates over time, but the UDS is what holds and grows in value, and it decides your compensation in any future redevelopment.

How is fair UDS calculated?

Fair UDS = (your flat’s super built-up area ÷ total saleable built-up area of all flats) × total land extent. If your 1,200 sq.ft flat is in a project with 60,000 sq.ft of total flats on 24,000 sq.ft of land, your fair UDS is 480 sq.ft.

What is a good UDS percentage?

It depends on how dense the project is. As a rule of thumb: in low-rise apartments (up to 3-4 floors) UDS of 40-50% of your flat area is healthy; in mid-rise projects 25-35% is typical; in high-rise towers 15-25% is normal because more flats share the same land. What matters most is that your UDS matches your proportional share — a low stated UDS relative to the fair calculation is the real red flag.

Where is UDS mentioned in my documents?

UDS is stated in your sale deed (often in the schedule of property), and it is what actually gets registered in your name. Cross-check it against this calculation before registration — once registered, correcting it is difficult.

Why does UDS matter for redevelopment and resale?

In redevelopment, your negotiating power and compensation are based on your UDS, not your flat size. In resale, especially of older buildings, buyers and banks increasingly value the land component. Two identical flats can have very different real values if their UDS differs.

Checking documents before you buy?

Calculate your registration cost too, and browse verified builder projects across Tamil Nadu.

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Disclaimer: This tool computes the proportional (fair) UDS and applies widely used rule-of-thumb health ranges. Actual UDS allocation can legitimately vary with project structure, common areas and approvals. Always verify the UDS in your sale deed with a property lawyer before registration.