🌾 Grain & Seed Screen Size Guide + Particle Size Converter

Complete reference for seed screen selection, mesh conversions, and particle sizes — all in one place.

📐 Understanding Screen Sizes

Learn how to read screen notations before selecting the right size for your crop.

📏 Reading Screen Sizes

Screen sizes are expressed in 64ths of an inch for round holes.

  • 14 = 14/64" round hole = 5.56 mm
  • 1/21 = 1/21" round hole = 1.21 mm

📐 Slot (Oblong) Screens

Written as Width × Length.

  • 1/13 × ½ = 1/13" wide × 1/2" long slot
  • = 1.95 × 12.7 mm

🔼 Top vs. Bottom Screen

  • Top Screen: Retains oversize material / debris.
  • Bottom Screen: Allows good seed to pass while removing fines.

🌾 Grain & Seed Screen Recommendations

Recommended top and bottom screen sizes for 80+ crops, seeds, and specialty products. All sizes include precise mm equivalents.

🔍

👉 Swipe horizontally to view all columns

Crop / SeedTop ScreenBottom Screen
Grains & Oils
Barley, plump9/64 × ¾
(3.57 × 19.05 mm)		5/64 × ¾
(1.98 × 19.05 mm)
Barley, thin8/64 × ¾
(3.18 × 19.05 mm)		1/13 × ½
(1.95 × 12.7 mm)
Buckwheat14
(5.56 mm)		6/64 × ¾
(2.38 × 19.05 mm)
Canola8
(3.18 mm)		1/19
(1.34 mm)
Corn, Field30
(11.91 mm)		14
(5.56 mm)
Cottonseed, acid delinted18
(7.14 mm)		9/64 × ¾
(3.57 × 19.05 mm)
Cottonseed, mechanically delinted20
(7.94 mm)		9½/64 × ¾
(3.77 × 19.05 mm)
Flax, large1/13 × ½
(1.95 × 12.7 mm)		6
(2.38 mm)
Millet, Proso8
(3.18 mm)		1/16
(1.59 mm)
Millet, Siberian6
(2.38 mm)		1/15
(1.69 mm)
Milo, Maize12
(4.76 mm)		1/12 × ½
(2.12 × 12.7 mm)
Oats, large18
(7.14 mm)		1/14 × ½
(1.81 × 12.7 mm)
Popcorn19
(7.54 mm)		11
(4.37 mm)
Rice, unhulled, long grain14
(5.56 mm)		1/16 × ½
(1.59 × 12.7 mm)
Rye12
(4.76 mm)		1/16 × ½
(1.59 × 12.7 mm)
Safflower11/64 × ¾
(4.37 × 19.05 mm)		6/64 × ¾
(2.38 × 19.05 mm)
Sesame1/20 × ½
(1.27 × 12.7 mm)		6 × 24
(2.38 × 9.53 mm)
Sorghum10
(3.97 mm)		1/15
(1.69 mm)
Spelt (Hulled)16
(6.35 mm)		5 × ¾
(1.98 × 19.05 mm)
Spelt (Unhulled)20
(7.94 mm)		6 × ¾
(2.38 × 19.05 mm)
Sunflower, Black Oil20
(7.94 mm)		11
(4.37 mm)
Sunflower, Large Stripped28
(11.11 mm)		13
(5.16 mm)
Wheat, plump14
(5.56 mm)		5½/64 × ¾
(2.18 × 19.05 mm)
Wheat, thin12
(4.76 mm)		1/13 × ½
(1.95 × 12.7 mm)
Wheat, Durum16
(6.35 mm)		6½/64 × ¾
(2.58 × 19.05 mm)
Small Legume Seed
Alfalfa1/14
(1.81 mm)		6 × 24
(2.38 × 9.53 mm)
Clover, Crimson1/13
(1.95 mm)		6 × 22
(2.38 × 8.73 mm)
Beans & Peas
Cranberry Beans30
(11.91 mm)		16/64 × ¾
(6.35 × 19.05 mm)
Great Northern Beans24
(9.53 mm)		11/64 × ¾
(4.37 × 19.05 mm)
Kidney Red Beans28
(11.11 mm)		14/64 × ¾
(5.56 × 19.05 mm)
Lima, Baby Beans30
(11.91 mm)		19
(7.54 mm)
Lima, Large Beans48
(19.05 mm)		26
(10.32 mm)
Pinto Beans24
(9.53 mm)		10/64 × ¾
(3.97 × 19.05 mm)
Black Turtle20
(7.94 mm)		9/64 × ¾
(3.57 × 19.05 mm)
Austrian Winter Peas17
(6.75 mm)		10/64 × ¾
(3.97 × 19.05 mm)
Black-eyed Peas24
(9.53 mm)		11/64 × ¾
(4.37 × 19.05 mm)
Canada Field Peas18
(7.14 mm)		9/64 × ¾
(3.57 × 19.05 mm)
Chick Peas, Garbanzos26
(10.32 mm)		12/64 × ¾
(4.76 × 19.05 mm)
Soybeans, Small (2800-3200/lb)18
(7.14 mm)		10/64 × ¾
(3.97 × 19.05 mm)
Soybeans, Medium (2500-2800/lb)20
(7.94 mm)		11/64 × ¾
(4.37 × 19.05 mm)
Soybeans, Large (2200-2500/lb)24
(9.53 mm)		12/64 × ¾
(4.76 × 19.05 mm)
Lentils7/64 × ¾
(2.78 × 19.05 mm)		11
(4.37 mm)
Tree Seed
Birch Black14
(5.56 mm)		6
(2.38 mm)
Cedar Red1/18 × ¼
(1.41 × 6.35 mm)		6
(2.38 mm)
Fir, Douglas15
(5.95 mm)		1/15 × ½
(1.69 × 12.7 mm)
Juniper22
(8.73 mm)		8/64 × ¾
(3.18 × 19.05 mm)
Locust, Honey20
(7.94 mm)		12
(4.76 mm)
Locust, Black10
(3.97 mm)		6
(2.38 mm)
Pine, Norway9
(3.57 mm)		1/13
(1.95 mm)
Spruce, Black1/13
(1.95 mm)		6 × 24
(2.38 × 9.53 mm)
Vegetable & Fruit
Asparagus12
(4.76 mm)		9
(3.57 mm)
Beet, California20
(7.94 mm)		8
(3.18 mm)
Broccoli7
(2.78 mm)		20 × 20
(7.94 × 7.94 mm)
Cabbage7
(2.78 mm)		1/17
(1.49 mm)
Celery1/17
(1.49 mm)		30 × 30
(11.91 × 11.91 mm)
Cucumber17
(6.75 mm)		9
(3.57 mm)
Carrot6
(2.38 mm)		6 × 28
(2.38 × 11.11 mm)
Muskmelon16
(6.35 mm)		9
(3.57 mm)
Onion9
(3.57 mm)		1/15
(1.69 mm)
Pepper17
(6.75 mm)		6/64 × ¾
(2.38 × 19.05 mm)
Radish9
(3.57 mm)		1/14
(1.81 mm)
Spinach8
(3.18 mm)		1/15
(1.69 mm)
Squash34
(13.49 mm)		22
(8.73 mm)
Watermelon24
(9.53 mm)		16
(6.35 mm)
Spice Seed
Basil6R
(2.38 mm)		6 × 24
(2.38 × 9.53 mm)
Cumin10
(3.97 mm)		6 × 28
(2.38 × 11.11 mm)
Mustard, Dark1/15
(1.69 mm)		6 × 22
(2.38 × 8.73 mm)
Pepper, Whole Black17
(6.75 mm)		6/64 × ¾
(2.38 × 19.05 mm)
Flower Seed
Aster8
(3.18 mm)		6 × 28
(2.38 × 11.11 mm)
Black-eyed Susan18 × 18
(7.14 × 7.14 mm)		6 × 36
(2.38 × 14.29 mm)
Calendula12
(4.76 mm)		6
(2.38 mm)
Daisy1/18 × ¼
(1.41 × 6.35 mm)		6 × 26
(2.38 × 10.32 mm)
Marigold1/15 × ¼
(1.69 × 6.35 mm)		6 × 34
(2.38 × 13.49 mm)
Petunia1/24
(1.06 mm)		50 × 50
(19.84 × 19.84 mm)
Specialty Crops
Tobacco Seed26 × 26
(10.32 × 10.32 mm)		60 × 60
(23.81 × 23.81 mm)
🔎 No crops match your search. Try a different keyword.

🔄 Particle Size Converter

Convert between US Mesh, millimeters, microns, and inches instantly.

Quick Conversion Tool

💡 Enter a value in any field to convert to other units automatically.

📏 What does "mesh" mean?

For smaller sieve sizes, the mesh number describes approximately how many openings occur along one linear inch of the sieve. A larger mesh number means a smaller opening and finer particles.

Example: A 40 mesh sieve has an opening of about 0.425 mm (425 µm).

➕ What do + and − mean?

  • +40 mesh: Particles retained by the 40-mesh sieve (larger than 425 µm).
  • -40 mesh: Particles that pass through the 40-mesh sieve (smaller than 425 µm).
  • -4 +40 mesh: Material that passes through 4 mesh but is retained by 40 mesh — roughly between 4.76 mm and 0.425 mm.

📊 Complete Sieve Conversion Table

Compare US Sieve (ASTM), Tyler Equivalent, Inches, Millimeters, and Microns.

🔍

👉 Swipe horizontally to view all columns

US Sieve (ASTM)Tyler EquivalentInchesMillimeters (mm)Microns (µm)
--5.0"125.0125,000
--4.24"106.0106,000
--4.0"100.0100,000
--3.5"90.090,000
--3.0"75.075,000
--2.5"63.063,000
--2.12"53.053,000
--2.0"50.050,000
--1.75"45.045,000
--1.5"37.537,500
--1.25"31.531,500
--1.06"26.526,500
--1.0"25.025,000
--0.875"22.422,400
--0.75"19.019,000
--0.625"16.016,000
--0.530"13.213,200
--0.50"12.512,500
--0.4375"11.211,200
--0.375"9.59,500
-2.5 Mesh0.312"8.08,000
-3 Mesh0.265"6.76,700
--0.250"6.36,300
No. 3 1/23.5 Mesh0.223"5.65,600
No. 44 Mesh0.187"4.754,750
No. 55 Mesh0.157"4.04,000
No. 66 Mesh0.132"3.353,350
No. 77 Mesh0.111"2.82,800
No. 88 Mesh0.0937"2.362,360
No. 1010 Mesh0.0787"2.02,000
No. 1212 Mesh0.0661"1.71,700
No. 1414 Mesh0.0555"1.41,400
No. 1616 Mesh0.0469"1.181,180
No. 1818 Mesh0.0394"1.01,000
No. 2020 Mesh0.0331"0.85850
No. 2525 Mesh0.0278"0.71710
No. 3030 Mesh0.0234"0.60600
No. 3535 Mesh0.0197"0.50500
No. 4040 Mesh0.0165"0.425425
No. 4545 Mesh0.0139"0.355355
No. 5050 Mesh0.0117"0.30300
No. 6060 Mesh0.0098"0.25250
No. 7070 Mesh0.0083"0.212212
No. 8080 Mesh0.0070"0.180180
No. 100100 Mesh0.0059"0.150150
No. 120120 Mesh0.0049"0.125125
No. 140140 Mesh0.0041"0.106106
No. 170170 Mesh0.0035"0.09090
No. 200200 Mesh0.0029"0.07575
No. 230230 Mesh0.0025"0.06363
No. 270270 Mesh0.0021"0.05353
No. 325325 Mesh0.0017"0.04545
No. 400400 Mesh0.0015"0.03838
No. 450--0.03232
No. 500--0.02525
No. 635--0.02020
📌 Please Note: Screen sizes are suggestions and will vary based on crop variety, moisture content, and field conditions. Mesh terminology and exact opening sizes can vary between sieve standards (ASTM vs. Tyler) and manufacturers. When ordering, please specify your two preferred screen perforation sizes in the comments field of your order.