INS Numbers Explained: International Coding System

What Is the International Numbering System?

The INS was developed by the Codex Alimentarius Commission — a joint program of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) — to provide a unified international system for identifying food additives. The system is published in the Codex Alimentarius's "Class Names and the International Numbering System for Food Additives" (CXS 192-1995).

The INS assigns a unique number to each food additive, organized by functional category. The numbers are broadly aligned with the European E-number system — for example, INS 202 and E202 both refer to potassium sorbate. However, the INS does not use the "E" prefix and includes some additives that may not be approved for use in the European Union. The INS serves as a reference numbering system; it does not itself authorize additives for use in any country.

INS vs E-Numbers: Key Differences

While the INS and E-number systems are closely related, there are important distinctions that consumers and food professionals should understand:

A key principle to remember: all E-numbers have corresponding INS numbers, but not all INS numbers have E-number equivalents. An additive may have an INS number but not be approved for food use in the EU, meaning it would not have an E-number.

INS Number Categories and Ranges

The INS organizes additives by functional category, using the same numbering ranges as the E-number system:

Complete INS Reference: Most Common Food Additives

Colors (INS 100–199)

Preservatives (INS 200–299)

Antioxidants and Emulsifiers (INS 300–499)

Flavor Enhancers and Sweeteners (INS 600–999)

How Different Countries Use the INS

The INS serves as the international reference, but countries implement it differently in their food labeling regulations:

European Union

EU food labels use E-numbers, which are derived from the INS. All EU-approved food additives have E-numbers. The EU maintains a positive list (Annex II of Regulation 1333/2008) of authorized additives with their E-numbers, permitted food categories, and maximum levels.

United States

The FDA does not use the INS or E-number system on food labels. Additives are listed by their common or usual name (e.g., "monosodium glutamate" rather than "INS 621" or "E621"). Colors are listed as "FD&C Yellow No. 5" or similar. However, the FDA's regulatory framework is compatible with the INS at a technical level, and the same additives are generally permitted.

Japan

Japan maintains its own additive coding system but largely aligns with the INS. Japanese food labels may use additive names rather than numbers. Japan has a positive list system (like the EU) rather than a GRAS system (like the US).

Australia and New Zealand

Food Standards Australia New Zealand (FSANZ) uses INS numbers on food labels, typically without the "E" prefix. Labels may show the additive name and/or the INS number in parentheses.

China

China uses a national standard (GB 2760) that references the INS. Chinese food labels may include INS numbers or additive names in Chinese.

India

India's Food Safety and Standards Authority (FSSAI) uses INS numbers for food additive identification, consistent with Codex Alimentarius standards.

The Codex Alimentarius and Global Food Safety

The Codex Alimentarius Commission was established in 1963 by the FAO and WHO to develop international food standards, guidelines, and codes of practice. The General Standard for Food Additives (GSFA, CXS 192-1995) is the Codex reference document that lists all INS-numbered additives, their permitted uses, and maximum levels in specific food categories.

Codex standards serve as the reference for international food trade under the World Trade Organization's Sanitary and Phytosanitary (SPS) Agreement. When countries dispute food safety measures that affect trade, Codex standards are used as the benchmark. This makes the INS system critically important for international food commerce — a manufacturer exporting to multiple countries must ensure compliance with each destination's regulations, all of which are ultimately referenced to the INS.

JECFA and Safety Evaluation

The Joint FAO/WHO Expert Committee on Food Additives (JECFA) provides independent scientific advice on food additives. JECFA evaluates the safety of additives and establishes ADI values that are used as reference points by regulatory agencies worldwide. JECFA's evaluations feed into Codex standards and the INS.

While EFSA (EU), FDA (US), and JECFA (international) often reach similar conclusions, they sometimes differ. For example, JECFA established an ADI of 0–40 mg/kg bw/day for aspartame, while EFSA set the same value but the FDA's acceptable daily intake is 50 mg/kg bw/day. These differences reflect variations in how each body interprets scientific data and applies safety factors.

Using INS Numbers as a Consumer

For consumers, the INS system provides a way to identify additives regardless of the country where a food product was manufactured. Here's how to use INS numbers effectively:

1. Recognize that INS and E-numbers are interchangeable — INS 202 is the same additive as E202 (potassium sorbate).
2. Check food labels for numbers — labels in some countries show INS numbers; EU labels show E-numbers.
3. Use our Food Additive Safety Checker — enter either the INS number, E-number, or additive name to get complete safety information.
4. Be aware of regulatory differences — an additive with an INS number may be permitted in some countries but not others.
5. Understand functional categories — knowing that INS 200-range numbers are preservatives and 600-range are flavor enhancers helps you quickly assess a product's additive profile.

Additives With INS Numbers But No E-Number

Some additives have been assigned INS numbers by Codex but are not approved in the EU, meaning they lack E-numbers. These include:

• INS 234 (Nisin): Has E234, approved in EU — actually this one does have an E-number.
• INS 925 (Dimethyl dicarbonate): Used as a beverage preservative; has an INS but limited EU approval.
• INS 926 (Dilauryl thiodipropionate): Antioxidant; no E-number (not approved in EU).
• INS 1201 (Polyvinylpyrrolidone): Stabilizer; no E-number for food use in EU.

Consumers encountering an unfamiliar INS number should use our Food Additive Safety Checker to determine whether it corresponds to an E-number and what its safety profile is.