# Moisture correction

> Moisture correction converts a lab result from as-received to dry-weight basis using the sample's measured water content, usually from a loss-on-drying test.

- Canonical: https://genetixbay.com/knowledge/glossary/moisture-correction.html
- Also written: moisture-corrected, moisture adjustment, loss on drying, LOD (loss on drying), moisture content test, moisture analysis
- Glossary category: Lab testing · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Moisture correction is the arithmetic step that removes water from the denominator of a result. The lab first measures [moisture content](https://genetixbay.com/knowledge/glossary/moisture-content.md), most often by loss on drying: a weighed portion is dried under controlled conditions until its weight stops falling, and the loss is taken as water (plus some volatile [terpenes](https://genetixbay.com/knowledge/glossary/terpene.md), a known small bias). The as-received result is then divided by (1 - moisture fraction).

## In practice

[Total THC](https://genetixbay.com/knowledge/glossary/total-thc.md) 18.6% [as received](https://genetixbay.com/knowledge/glossary/dry-weight-basis.md), moisture 10.5%: corrected = 18.6 / 0.895 = 20.8% dry weight. The higher the moisture, the bigger the correction. A wet sample tested as received [looks](https://genetixbay.com/knowledge/glossary/bag-appeal.md) weaker; the same sample moisture-corrected looks stronger. Moisture is also a quality signal: [cured](https://genetixbay.com/knowledge/glossary/curing.md) flower around 10-12% w/w moisture with [water activity](https://genetixbay.com/knowledge/glossary/water-activity.md) about 0.55-0.65 is in the safe, well-cured range.

## Units and formula

Corrected (% w/w dry) = as-received (% w/w) / (1 - moisture %/100).

## Don't confuse with

- **Water activity test**: measures free water availability (aw), not total water mass.
- **LOD (limit of detection)**: same abbreviation as loss on drying, different meaning.

## Myth check

Always check whether moisture correction was applied before comparing numbers. See [buyer beware](https://genetixbay.com/knowledge/basics/buyer-beware-label-claims.md).

## Related terms

[Dry-weight basis](https://genetixbay.com/knowledge/glossary/dry-weight-basis.md), [Water activity test](https://genetixbay.com/knowledge/glossary/water-activity-test.md), [Potency testing](https://genetixbay.com/knowledge/glossary/potency-testing.md), [COA](https://genetixbay.com/knowledge/glossary/coa.md)

## Read more

- [Buyer beware: potency labels, strain names and other claims that don't hold up](https://genetixbay.com/knowledge/basics/buyer-beware-label-claims.md)
- [Curing and burping: jars, humidity and how long](https://genetixbay.com/knowledge/harvest-cure/curing-burping.md)