How to Measure Your Land from the Mouza Map on Your Phone

"The deed says 12 decimals, but the plot doesn't look that big." Anyone who has bought, sold or divided land in Bangladesh has heard some version of that doubt. The first place to look for an answer is the Mouza map: the government survey sheet that draws every plot (dag) in a mouza, with its number. If you know the map's scale, you can work out a plot's area from its shape.

On a paper map that takes a ruler, a scale and a lot of arithmetic. On a scanned Mouza map on your phone, you tap the corners and the area appears in decimals, katha and bigha. Getting a result you can trust still depends on a few things, and that is what this guide covers.

What a Mouza map is, and which one you need

Mouza maps are survey sheets prepared by the Directorate of Land Records and Surveys (DLRS). Each one shows the plots, roads, canals and boundaries of one mouza. The same mouza can have maps from several surveys, CS, SA, RS and BS, and plot numbers changed between them. So you need the map from the same survey as the plot number on your deed or khatian.

Mouza maps exist for all 61 surveyed districts. The three Chittagong Hill Tracts districts, Khagrachari, Bandarban and Rangamati, were never cadastrally surveyed, so they have none, and some districts only have maps for some upazilas.

Step by step: a plot's area from the Mouza map

1. Find the right map

Work down from division to district, upazila, survey (CS, SA, RS or BS) and mouza. Before downloading, look at the sheet once to confirm your plot number is actually on it.

2. Identify the map's scale

This is the step that matters most, because the area can only be as accurate as the scale. The scale is usually printed near the title, and it is one of four: 16, 32, 64 or 80 inches to the mile. Most sheets are 16 inches. Pick the wrong one and the area comes out four times too big or too small, or worse, so always read the printed scale yourself.

3. Check it against the chain scale bar

Old paper shrinks, and a scan can be slightly enlarged or reduced. So rather than trusting the printed scale alone, measure the chain scale bar drawn on the sheet and see if it matches. If it does, good; if it doesn't, calibrate the map from the scale bar instead.

4. Trace the plot corner by corner

Zoom in until the printed boundary lines are a few pixels thick. Then place a point at each corner, in the middle of the line, not on its edge, and work your way round until you are back at the start.

5. Read the area and compare it with the deed

Read the area in decimals, katha, bigha, acres or square feet, and compare it with the deed or khatian. A small difference is normal. If it is large, check the scale and the survey again first, then talk to an amin.

Land units at a glance

• 1 decimal (শতক, shotok) = 435.6 sq ft = 1/100 of an acre
• 1 acre = 100 decimals = 43,560 sq ft
• 1 katha (কাঠা) = 720 sq ft, about 1.65 decimals
• 1 bigha (বিঘা) = 20 katha = 14,400 sq ft, about 33 decimals
• 1 kani (কানি) = 20 gonda; usually 40 decimals in Chittagong

Careful: bigha and kani vary from place to place. Find out how many decimals make a bigha where your land is, or the same plot will sound like two different sizes in two different villages. In the app, both can be set to match your area in Settings.

The four most common mistakes

• The wrong scale. Treat a 32-inch map as 16-inch and the area comes out four times too big. Always read the printed scale yourself.
• The wrong survey's map. Look up a CS plot number on a BS map and you will measure someone else's land. Match the plot number and the survey.
• Corners on the edge of the line. Printed lines are thick; placing corners on their edge makes a noticeable difference on a small plot. Put them in the middle.
• Treating the result as final. This is a checking tool. For a sale or a dispute, the official survey and the amin's measurement are what count.

The short version

The right survey's map, the right scale, one check against the chain scale bar, and corners placed mid-line: get those four right and you can check a plot's area reliably on your phone. Having a number in hand before a purchase or a family discussion about shares answers a lot of questions. For the final decision, the official survey is what you rely on.

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Frequently asked questions