A kosher symbol is a certification mark — a trademark belonging to the organisation that did the supervising. Reading one comes down to three things: what the mark itself is, what the letters after it mean, and what none of it tells you.
A plain K means nothing on its own
Start here, because it is the most useful fact on this page. A single letter cannot be owned as a trademark for kosher, so a bare “K” is not a certification mark. Anyone can print one. New York, which regulates kosher labelling, treats a bare k as a generic kosher marking rather than a certification, and regulates it on that basis.
That is not a claim that products bearing a K are not kosher. Plenty are, certified by an organisation that simply uses a plain K as its mark. It is a claim about what the letter tells you: not who checked, not what they checked, not whether anyone did. Any of that has to be found out separately.
The shape is what makes a mark traceable
Almost every hechsher is a letter or letters inside a shape, and the shape is the point — it is what makes the mark ownable, and therefore what makes it possible to find out whose it is. A U inside a circle belongs to one organisation. A K inside a circle belongs to a different one. A K inside a star, a K inside a triangle, letters on a tablet: each belongs to somebody, and each means a different body did the work.
So the first question about a symbol you do not recognise is not “is this good?” It is “whose is it?” — and that one has an answer you can go and get.
The letters after the symbol
- D — dairy. Either it contains dairy, or it was made on dairy equipment.
- DE — dairy equipment. No dairy ingredients, but made on equipment that runs dairy. The practical consequence is about eating it after meat rather than with it.
- Pareve (or parve) — neither meat nor dairy. Note that it is written out.
- Meat, Glatt — meat; glatt refers to a standard in the lung inspection of the animal. What makes an animal treif
- P — Passover. Not pareve. This is the one that catches people every year. A symbol followed by P means certified for Pesach and says nothing at all about dairy. Pareve is spelled out; P is never short for it. Kosher for Pesach basics
- Cholov Yisroel, Pas Yisroel, Yoshon, Fish — additional standards, normally spelled out rather than abbreviated. Cholov yisroel · Pas yisroel · Yoshon
If the question is the symbol on your own packaging rather than someone else’s — which designation to print, where the mark may and may not appear, what happens when only some of your lines are certified — that is covered separately in kosher symbols explained.
What a symbol does not tell you
- That the product is still certified. Certification is granted per product and can lapse; packaging and artwork outlive it.
- That the symbol on the box is the one the agency issued. Marks are misused, which is why agencies publish their own certified lists and occasionally go to court over them.
- That it is a hechsher you rely on. This genuinely varies between communities, and it is the question to bring to your rav.
How to check a symbol you do not recognise
- Identify the organisation. The mark is a trademark and belongs to somebody.
- Go to that organisation's own site and search their certified list. Most publish one and keep it current.
- Look up the product, not just the company. A company is very often certified for some lines and not others, which is the most common reason a symbol on one package does not transfer to another from the same brand. Why a kosher species may not be certified
- If it is not listed, ask them. Certifiers answer this question all day.
- Then ask your rav whether it is a hechsher you rely on. This is the step we cannot do for you and would not try to: whether a given hechsher is relied upon is a matter for your rav and your community, and it is not for one certification agency to pronounce on another.
Some marks you will meet
This is an identification list, not an approval list. It covers marks whose identity is not in dispute, because identification is the only thing it is for. A mark that is not listed here has not been rejected — there are a great many certifiers and most of them are not on this page. If you meet one that is not here, the five steps above are how you check it. We do not rate hechsherim, including our own.
| Mark | Organisation | Reads as | Based | Verify at |
|---|---|---|---|---|
| OU | Orthodox Union | the letter U inside a circle | New York | oukosher.org |
| OK | OK Kosher Certification | the letter K inside a circle | Brooklyn, New York | ok.org |
| Star-K | STAR-K Kosher Certification | the letter K inside a star | Baltimore, Maryland | star-k.org |
| Kof-K | Kof-K Kosher Supervision | the Hebrew letter kuf with a K set inside it | Teaneck, New Jersey | kof-k.org |
| cRc | Chicago Rabbinical Council | the letters cRc | Chicago, Illinois | crckosher.org |
| KVH | Rabbinical Council of New England (Vaad Harabonim) | the letters KVH | Boston, Massachusetts | kvhkosher.org |
| Pure K | Pure K | the Pure K droplet mark | United States | purek.org |
Our own entry is there on the same terms as the rest, with the same absence of any claim about standing. Ask your rav about ours too.
Where to go from here
What is kashrus sets out what the symbol is actually certifying — the questions a hechsher exists to answer. Why a kosher species may not be certified covers the case where everything about a food is kosher and it still is not certified. For a particular product rather than a principle, the is-it-kosher answers answers the questions people actually ask.