Frozen Prawn Sizes and Count Grades Explained
Prawn size grades are usually expressed as the number of pieces within a stated unit of weight. A lower count generally means a larger prawn—but labels such as U/10, 16/20 or 31/40 are meaningful only when the quotation also states the unit, product form, raw or cooked condition, glaze basis, net weight and permitted tolerance.
What does a frozen prawn count grade mean?
A count grade describes how many prawns fall within a specified unit of product weight. For example, when a specification says 16/20 count per pound, it means the target range is sixteen to twenty prawns in one pound of the stated product form.
Because fewer large prawns are needed to make up the same weight, lower count numbers normally indicate larger individual prawns. Higher count numbers normally indicate smaller prawns.
Larger individual prawns
U/10 and 13/15 are larger than 21/25 when the unit and product form are the same.
More pieces per unit weight
41/50 contains more, smaller pieces than 16/20 under an equivalent counting basis.
“Under” the stated count
U/10 generally means fewer than ten prawns per stated unit, but the unit must still be shown.
How common count labels are interpreted
The examples below show a common count-per-pound interpretation used in international shrimp trade. They are educational examples rather than a universal official size table or a guaranteed list of sizes supplied by The Sea Marine.
| Example label | Literal meaning when stated per lb | Relative size | Possible commercial application |
|---|---|---|---|
| U/10 | Fewer than 10 pieces per pound | Extra large | Premium presentation, grilling or centre-of-plate use |
| 13/15 | 13 to 15 pieces per pound | Very large | Hotels, restaurants, banquets and display-focused dishes |
| 16/20 | 16 to 20 pieces per pound | Large | Food service, grilling, hotpot and plated dishes |
| 21/25 | 21 to 25 pieces per pound | Medium-large | Versatile restaurant, catering and retail applications |
| 26/30 | 26 to 30 pieces per pound | Medium | General food service, stir-fry and mixed dishes |
| 31/40 | 31 to 40 pieces per pound | Medium-small | Catering, ready meals and value-focused menu use |
| 41/50 | 41 to 50 pieces per pound | Smaller | Rice, noodles, pasta, fillings and prepared-food production |
| 51/60+ | 51 or more pieces per pound, according to the stated range | Small | Ingredient use, value-added products and portion-controlled mixes |
Count per pound and count per kilogram are not the same
U.S. and some international seafood trade documents commonly express shrimp size as the number of pieces per pound. Malaysian, Asian and other commercial quotations may instead use pieces per kilogram—particularly for certain whole or head-on formats. Neither basis should be assumed.
This is not the same size as 16/20 per kilogram. The unit should appear in the quotation, specification sheet, label or carton marking.
This describes a metric count range. It should not be shortened to “30/40” in a purchase order unless both parties have already agreed the unit.
A mathematical conversion is possible: count per kilogram ≈ count per pound × 2.2046. However, converted ranges may not match the market’s normal commercial bands, so a buyer should not relabel a grade without agreement.
The same biological prawn changes grade after processing
Removing the head, shell or moisture changes the product weight. Therefore, HOSO, HLSO, peeled and cooked products cannot be compared by count label unless the product form and counting basis match.
Head-On, Shell-On
Whole-prawn weight includes the head and shell. State whether the size is counted per kilogram or per pound.
Headless, Shell-On
Head removal reduces piece weight, so the count grade will not directly match the original HOSO grade.
Peeled, Undeveined
Shell removal further changes the count-to-weight relationship. The approved specification should define peeling and tail condition.
Peeled, Deveined
State the deveining method, tail condition, cut and acceptable defects together with the count range.
Peeled, Tail-On
Tail retention affects piece weight and presentation. Confirm whether the product is deveined and how the cut is made.
Cooked Product
Cooking can change weight and texture. Raw and cooked count grades should not be compared without a matched specification.
Count grade should be tied to actual prawn weight
Glazing is a protective ice coating used on frozen seafood. A buyer should clarify whether count verification is performed before glazing, after deglazing, or using another agreed method. The declared net product weight should not be confused with gross pack weight or added protective ice.
| Field | What to state | Why it affects the grade |
|---|---|---|
| Count unit | Pieces per pound or pieces per kilogram | Changes the numerical meaning of the same written range |
| Product form | HOSO, HLSO, PUD, PD, PTO or another full description | Head and shell removal change piece weight |
| Raw / cooked | State the processing condition | Cooking changes moisture, weight and texture |
| Glaze basis | Glazed or unglazed and count-verification method | Protective ice must not distort the actual product comparison |
| Net weight | Actual prawn product weight under the agreed method | Determines price and piece-count calculation |
| Tolerance | Sampling method and permitted out-of-range pieces | A range alone does not define lot acceptance |
| Broken pieces | Definition and allowable percentage | Broken material can alter piece count and usable presentation |
Malaysia and international standards relevant to prawn grades
Count grades are commercial product specifications. They must operate together with food law, aquaculture controls, hygiene, labelling, freezing, net-content and destination-market requirements.
Codex CXS 92-1981
The international standard covers quick-frozen raw, partially cooked or fully cooked prawns, peeled or unpeeled. It addresses product presentation, size designation, freezing, glazing, net contents, hygiene and labelling.
View the Codex prawn standard ↗NOAA Shrimp Size Classes
NOAA fisheries data describes shrimp size categories as ranges of the number of shrimp per pound, supporting the common U.S. market interpretation of count-per-pound grades.
View NOAA size-class metadata ↗Malaysia Food Regulations 1985
Malaysia’s food regulations establish relevant product, additive, net-content and labelling controls. Current provisions and amendments must be checked for the actual product and market.
View Ministry of Health regulations ↗Malaysia Food Hygiene Regulations 2009
Food premises and activities including preparation, handling, storage, packaging and transport are subject to applicable hygiene requirements.
View Ministry of Health hygiene rules ↗Department of Fisheries Malaysia
DOF publishes codes of good aquaculture practice for marine shrimp farming and hatcheries. These production standards do not create one universal wholesale count table.
View official aquaculture codes ↗Destination-Market Requirements
Importer specifications, product names, size declarations, permitted treatments, residues, labels, health certificates and establishment requirements vary by destination.
Review seafood export support →What an international buyer should include in an RFQ
A complete enquiry allows a supplier to compare the requested grade with available harvest, processing, packing and certification scope.
- Black Tiger, Vannamei or another identified species
- Common and scientific species name
- HOSO, HLSO, PUD, PD, PTO or other product form
- Raw, partially cooked or fully cooked status
- Count range and unit: per lb or per kg
- Count sampling and tolerance method
- IQF, block frozen or another frozen format
- Glazed or unglazed specification
- Declared net product weight
- Broken, damaged and out-of-range tolerance
- Inner pack and master-carton configuration
- Bulk, food-service, retail or private-label requirement
- Lot code and traceability records
- Storage temperature and shelf-life requirement
- Certificate holder, premises and applicable scope
- Destination-market documents and label requirements
Choose the grade for the intended use
Size should support the desired appearance, portion cost, usable yield, cooking method and kitchen or factory workflow.
Hotels & Restaurants
Larger, consistent grades may support visual presentation and controlled portions, while the correct product form can reduce preparation labour.
Catering & Central Kitchens
Medium grades may balance piece count, cost, batch preparation and menu versatility for large-volume service.
Wholesale Distribution
Distributors often need recognised count ranges, clear carton markings and stable pack formats for downstream customers.
Retail Packs
Pack size, visible piece count, glaze, label claims and consumer cooking use should be aligned before production.
Ready Meals & Processing
Smaller or medium grades can support ingredient distribution, but count consistency and broken-piece tolerance remain important.
Private Label
The approved artwork should match the actual species, product form, count unit, net weight, storage and destination requirements.
Black Tiger and Vannamei prawn enquiries
The Sea Marine’s current product range includes Black Tiger Prawn (Penaeus monodon) and Vannamei Prawn (Litopenaeus vannamei), together with chilled, frozen, IQF, food-service and buyer-specified packing options. Final size grades and formats remain subject to written availability and product specifications.
Buyers can review our prawn and frozen seafood products, read the Vannamei wholesale and food-service guide, compare IQF seafood processing, and examine farm-to-freezer traceability.
Linked prawn and seafood buyer resources
Frequently asked questions
Does a lower prawn count mean a larger prawn?
Yes, when the unit, species, product form and condition are the same. Fewer pieces are needed to make up the stated weight, so each piece is generally larger.
What does U/10 mean?
“U” means under. U/10 generally means fewer than ten prawns in the stated unit of weight. The quotation must still say whether that unit is one pound, one kilogram or another agreed basis.
Is 16/20 per kilogram the same as 16/20 per pound?
No. Sixteen to twenty pieces per pound are much smaller in total unit weight than sixteen to twenty pieces per kilogram. Omitting the unit creates a serious specification risk.
Can HOSO and peeled prawns have the same count grade?
They may show similar numbers in separate specifications, but they are not directly comparable because removing the head and shell changes the piece weight.
Does glazing affect count grade?
It can affect measurement if the counting method is not defined. Buyers should state whether count and net weight are verified on deglazed product or another agreed basis.
Which count grade is best for food service?
There is no universal best grade. The decision depends on menu presentation, serving size, labour, cooking method, usable yield and target food cost.
What should I send for a frozen prawn quotation?
Send the species, product form, raw or cooked condition, count range and unit, quantity, glaze, net weight, packaging, destination, certifications and shipment period.
Sources used for this guide
Standards and regulations change. Review the current official version and the requirements applicable to the exact product, premises, certificate and destination.
- Codex CXS 92-1981 — Standard for Quick-Frozen Shrimps or Prawns
- NOAA Fisheries — Shrimp Size-Class Ranges by Count per Pound
- NOAA Fisheries — Gulf Shrimp Size Categories
- Ministry of Health Malaysia — Food Regulations 1985
- Ministry of Health Malaysia — Food Hygiene Regulations 2009
- Department of Fisheries Malaysia — Marine Shrimp Aquaculture Standards and Codes