Five calculators surveyors use every week, in one Excel workbook. Type your field data in d.mmss and metres, and get adjusted results with built-in checks.
Instant download after payment. Secure checkout by Paddle, our reseller and Merchant of Record.
Traverse: Bowditch adjustmentExample data
Stn
Bearing
Dist (m)
Adj E
Adj N
B
45.0000
100.000
1070.707
5070.709
C
135.0010
100.020
1141.424
4999.980
D
225.0005
99.980
1070.722
4929.284
A
315.0000
100.010
1000.000
5000.000
Linear misclosure0.0169 m
Precision1 : 23,614
What's inside
Five calculators, one workbook
Traverse adjustment
Bowditch (compass rule) adjustment with linear misclosure, misclosure bearing, precision ratio and adjusted coordinates.
Up to 20 legs
Area from coordinates
Area in square metres, hectares and acres, plus perimeter, using the coordinate (shoelace) method.
Up to 50 points
Levelling reduction
Rise and fall method with BS, IS and FS columns, change points, and automatic arithmetic checks.
Up to 40 readings
COGO join and polar
Bearing and distance between two points, or new coordinates from a bearing and distance.
10 rows each
Angle and unit converter
d.mmss to decimal degrees and radians and back, plus square metres, hectares and acres.
DMS · DEC · RAD
Metric, d.mmssAngles entered the way you book them
Locked formulasOnly the yellow input cells are editable
Example dataEvery sheet comes filled in so you learn it fast
.xlsx fileWorks in Microsoft Excel and most spreadsheet apps
Questions
Before you buy
What do I receive?
One Excel workbook (.xlsx) delivered as an instant download link by email after payment.
Which software do I need?
Microsoft Excel 2010 or later. Most features also work in LibreOffice Calc and Google Sheets.
Can I use it for client work?
Yes. Your licence covers use in your own professional work. Please don't resell or share the file. Always check results against your own field checks before using them in final deliverables.
Can I get a refund?
Because the toolkit is a digital download you keep once delivered, all sales are final. If the file is faulty and we can't fix it, we'll refund you. Please check the example screenshots and calculator list before buying. See the refund policy.
Contact
Get in touch
For questions about the toolkit, licensing or your order, email support@dekhairtools.com. We reply within two working days.
De' Khair Enterprise · Business No. P30001133 · Brunei Darussalam
Terms of service
Last updated: 27 October 2026
These terms apply to purchases of digital products from De' Khair Survey Tools, operated by De' Khair Enterprise (Business No. P30001133), Brunei Darussalam ("we", "us").
Our reseller
Our order process is conducted by our online reseller Paddle.com. Paddle.com is the Merchant of Record for all our orders. Paddle provides all customer service inquiries and handles returns.
Products
We sell downloadable Excel workbooks for land surveying calculations. Product descriptions on this site describe what each file contains. Files are delivered electronically after payment is confirmed.
Licence
When you buy a product, you receive a non-exclusive, non-transferable licence for one person to use the file in their own personal or professional work. You may not resell, share, redistribute or publish the file or modified versions of it.
Accuracy and responsibility
The toolkit is a calculation aid. You are responsible for checking inputs and results against your own field checks and professional standards before relying on them. To the extent permitted by law, we are not liable for losses arising from the use of results produced by the files.
Refunds
All sales are final once the file has been delivered, except for faulty files and where your local law gives you a right to a refund. See our refund policy.
Changes
We may update these terms. The version in force at the time of your purchase applies to that purchase.
Governing law
These terms are governed by the laws of Brunei Darussalam, without affecting any consumer rights you have in your own country.
Contact
Email support@dekhairtools.com.
Refund policy
Last updated: 27 October 2026
Our products are digital downloads that you can keep and use as soon as your order is complete. For this reason, all sales are final and we do not offer refunds for change of mind, or once the file has been downloaded.
Faulty files
If the file will not open, or a calculator does not work as described, contact us within 14 days of purchase with your order number and a short description of the problem. We will send a fix or a replacement file. If we cannot fix it, we will refund your purchase in full.
Your legal rights
Nothing in this policy affects any rights you have under the consumer laws of your country. Where those laws give you a right to cancel or a refund, that right applies. By completing your purchase, you agree that delivery of the digital file starts immediately and, where the law allows, that you lose any right to cancel once the download has started.
How to contact us
Email us at support@dekhairtools.com with your order number. Our orders are processed by Paddle.com, our reseller and Merchant of Record, and any approved refund is issued by Paddle to your original payment method. You can also reach Paddle through the support link in your order receipt or at paddle.net.
Your bank or card provider may take several working days to show an approved refund.
Privacy policy
Last updated: 27 October 2026
This policy explains how De' Khair Enterprise ("we") handles personal information when you visit this site or buy our products.
Information we collect
Order details shared with us by Paddle, such as your name, email address, country and the product you bought.
Messages you send us by email.
Payments are processed by Paddle.com, our Merchant of Record. We never see or store your full card details. Paddle's own privacy policy applies to the information you give during checkout.
How we use it
To deliver your purchase and provide support.
To respond to your questions.
To keep business and accounting records.
We do not sell your personal information. We only send marketing emails if you have agreed to receive them, and you can unsubscribe at any time.
Keeping and deleting data
We keep order records for as long as needed for support and accounting. You can ask us to access, correct or delete your information by emailing support@dekhairtools.com.
Changes
We may update this policy. The latest version is always on this page.