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Drilling Fluid Calculator

Calculate bentonite quantities for drilling mud preparation. Light, medium, and heavy mix ratios for different ground conditions.

Last updated 5 March 2026

About this tool

Calculate the amount of bentonite powder needed to prepare drilling mud. Choose from light, medium, or heavy mix concentrations based on ground conditions and drilling requirements.

Revision history

5 March 2026: Initial release with light/medium/heavy presets, custom ratio, and mud density calculation.

Disclaimer

This tool is provided for educational and general information purposes only. It is not a substitute for professional engineering advice, design or verification.

Diggy and its contributors are not licensed engineering consultants and no results generated by this tool should be used directly for construction, design or safety-critical decisions.

All values and outputs are based on published empirical correlations and should be independently checked and confirmed by a qualified geotechnical engineer before use.

By using this tool, you accept full responsibility for how you interpret and apply the information provided.

Spotted an error? Let us know.

Water volume (litres)

Mix concentration

Standard drilling mud

Bentonite bag size (kg)

Typical applications

Light: Initial stabilisation, good ground

Medium: General rotary drilling

Heavy: Unstable formations, water control

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