Buying guide

Moisture content standards for wheat, rice, paddy and maize in Pakistan

Reviewed 8 September 2026

Moisture content is the weight of water in the grain, expressed as a percentage of the total weight. Grain at 14 percent moisture is 14 percent water by weight. The laboratory reference method is oven drying: weigh a sample, bake it until all the water is gone, weigh it again, and the weight lost is the water. That is accurate but slow, so in the field and at the buying point everyone uses an electronic moisture meter, which reads an electrical property of the grain and converts it to a percentage in seconds. How that works, and why each grain needs its own setting, is covered in our guide on how to choose a grain moisture meter.

One point that trips people up: a meter reads differently for each crop even at the same true moisture, because kernels pack and hold water differently. That is why you must select the correct grain on the meter before you read, and why the calibration count matters, as explained in what the parameters mean. A wheat reading taken with the meter set to paddy is simply wrong.

For safe long-term storage, wheat is commonly kept at or below about 12 percent moisture. Around this level the grain is stable: mould and storage insects struggle, and the wheat can sit in a store or godown for months without heating. As moisture climbs above roughly 13 to 14 percent the risk rises quickly, and grain held wet in a sealed heap will heat, cake and spoil from the inside.

Procurement matters here too. Government and commercial wheat buyers set a maximum moisture they will accept, often in the region of 12 percent, and grain above the limit is either discounted, dried at your cost, or turned away. This is not a figure to guess at. A tenth of a percent can sit either side of a price break, so a reliable reading before you load pays for the meter many times over. Confirm the exact procurement limit with your buyer for the season, then measure against it.

Paddy (rough rice, still in the husk) is the trickiest of the staples, because it comes off the field wet. Freshly harvested paddy can be 20 to 25 percent moisture or higher, far too wet to store, and it must be dried down promptly or it will spoil within a day or two in a heap. For safe storage, paddy is commonly brought down to around 14 percent, and for longer holding a little below that.

Drying rate matters as much as the final number for paddy. Dry it too fast or too hard and the kernels crack, which lowers the head rice yield (the proportion of whole unbroken grains after milling) and cuts the price the mill will pay. So paddy is a balance: dry promptly enough to prevent spoilage, gently enough to protect the grain. Milled white rice is usually held around 12 to 14 percent for storage and trade. Because paddy and milled rice pack so differently, make sure your meter has a separate calibration for each and that you select the right one.

Maize (corn) is the crop where moisture control is most about safety, not just quality. Maize is harvested wet, often 20 to 30 percent or more, and damp maize is highly prone to aflatoxin, a toxin produced by mould that makes the grain unsafe for food and feed and gets loads rejected on testing. For safe storage, maize is commonly dried to around 13 to 14 percent, and buyers who test for aflatoxin are strict about wet grain for exactly this reason.

The lesson with maize is speed. The gap between harvest moisture and safe storage moisture is wide, and the longer the grain sits wet and warm, the greater the aflatoxin risk. Measure early, dry promptly, and confirm the grain is at target before it goes into store. A meter that reads the wet end of the range accurately is worth having here, so check the meter's moisture range, not just its grain count.

These are typical safe-storage rules of thumb, not a specification. Confirm procurement and export limits with your buyer.

• Wheat: commonly stored at or below about 12 percent; procurement limits often around 12 percent.
• Paddy (rough rice): harvested at 20 to 25 percent or more, dried to about 14 percent for storage.
• Milled rice: commonly held around 12 to 14 percent.
• Maize: harvested very wet, dried to about 13 to 14 percent; keep dry to limit aflatoxin risk.

Two things happen when grain is wetter than target. First, safety and quality fall: the grain heats, moulds, loses germination and can grow toxins, and a buyer who tests will discount or reject it. Second, you are selling water as if it were grain, which the buyer knows, so they price the moisture out or dock the weight. On the other side, over-drying below target means you have evaporated weight you would have been paid for. The target is the sweet spot where the grain is safe and you are paid for grain, not water. Hitting it consistently needs measurement, not judgement by hand or tooth.

A single reading off one scoop can mislead, because moisture varies through a heap. Do this instead:

1. 1.Select the correct grain on the meter first. A wheat reading on the paddy setting is meaningless.
2. 2.Take three to five samples from different depths and points in the lot, and average the readings.
3. 3.Let very cold or sun-hot grain settle toward room temperature, or use a meter with temperature compensation, because temperature shifts the reading.
4. 4.Keep the sample clean of stones, chaff and dust, and keep the chamber or probe clean between readings.
5. 5.For a load going into a contract, check against the buyer's meter where you can, and use an offset if your meter allows one to bring the two into line.

For a rod-type meter you can push into a sack or heap, our MC-7821 reads without drawing a separate sample. For a wide crop mix the 7825G with 30 grain calibrations covers wheat, paddy, rice and maize and much more. Where the reading goes into a contract or a seed certificate, a professional chamber meter such as the Wile 55 from Finland or the Agratronix MT-16 from the USA gives the repeatability you can stand behind.

Every meter linked here is stocked at our Lahore shop, brand new box pack, and you can see the full range on the grain and hay moisture meters page. We stock the meters, not the standards: the target percentages above are general agronomic figures, and the binding numbers for a sale are whatever your mill, food department or exporter sets. If you tell us the crops you handle and how you sell, we will point you to a meter with the right coverage and accuracy for the targets you need to hit. If you need a specific model we do not carry, message us and we will tell you honestly whether we can source it or which meter we stock comes closest.