How the Five Compare on the Numbers
Fermenting several things at once is a counting problem before it is anything else. A jar under an airlock is occupied for one to four weeks, so a household that wants sauerkraut and kimchi and pickles running together needs that many lids, and the number in the title is the specification that decides it.
These five equip anywhere from two jars to six. The counts are not directly comparable, because one purchase equips gallon jars rather than quart jars, one fits regular mouth rather than wide mouth, and two purchases publish a grommet or airlock count that does not match the lid count. Thirty listings sit behind this page.
What the table cannot tell you is how many jars any of these will equip a year from now. Every one of these systems has a soft component that wears, a silicone grommet or a rubber seal, and only one of the five publishes anything about replacing it. A count that drops to five working lids after a season is not the count you bought.
Two Purchases That Equip Six Jars
Six Lids, Six Airlocks and Spares
JILLMO publishes the cleanest count on this page: six stainless steel lids with seals, six BPA free airlocks and six silicone grommets, with extra grommets in the box. It states the fit precisely, at 3.38 in and again as 86 mm for a standard wide mouth jar, and names the jar range as 8 oz to 64 oz.
It is also the only pick that addresses what happens when a small piece fails, publishing a one year replacement for damaged small parts alongside the spare grommets. Its washing rule is specific in a useful direction: warm water only on the plastic airlocks, and an instruction not to boil them. It publishes 0.84 lb for the whole kit.
Six Lids and a Grommet Count That Disagrees With Itself
Klemon also equips six jars and describes the parts more fully: six stainless lids given as 18/8 with silicone rings, six BPA free water airlocks, and a three piece airlock design that can be taken apart and brushed out. It names a wider jar range than JILLMO, from 4 oz to 64 oz.
Its own title and its own first bullet disagree on one number. The title says six silicone grommets and the bullet says nine. Nine against six lids is the more useful reading, because it means three spares, but the listing never reconciles the two and this page reports both rather than picking one. It publishes 0.9 lb.
Four, Three and Two, and What You Give Up
Four Lids and One Pump Between Them
FERMENTER LIDS equips four jars with a different mechanism: rather than a water airlock, each lid carries a vacuum seal valve with a release tab, and the purchase includes one oxygen extraction pump for drawing air out and a date setter built into the lid. The pump is one object shared across four jars.
That is a real difference for batch work. A water airlock has to be topped up and cannot be tipped; a valve does not. What the listing gives up is precision elsewhere: it publishes 3.62 x 3.62 in with no third figure, names no material beyond BPA free, and says only that the lids fit most wide mouth mason jars.
Three Regular Mouth Lids and Two Gallon Lids
MiniMunch is the only regular mouth pick here and says so twice, stating 70 mm regular mouth and warning that the lids are not sized for 80 mm wide mouth jars. Each is one piece of food grade silicone with a self burping vent, and each needs a metal screw band you already own, which the listing states plainly.
Fermentaholics goes the other way. Two lids, but each one turns a 110 mm gallon jar into a fermenter, with a silicone gasket, a rubber grommet and an S airlock supplied per lid. Two gallon jars is a great deal more cabbage than six quart jars, so the fewest lids here does not mean the least volume.
What the Count Does Not Tell You
Two Listings in This Pool Are Not Fermentation Lids
The largest count in the whole pool belongs to a purchase this page leaves out. EcoPeaceful publishes twelve wide mouth lids with silicone gaskets, calls the total twenty four pieces, and publishes 316 surgical stainless steel with a range of minus 40 F to 425 F. It is a storage lid. There is no vent and no airlock, and its own bullet says not for canning.
SSIBOOTO is the same case at four lids: food grade silicone, leak proof, a stated tolerance from minus 40 F to 446 F, and no vent of any kind. A sealed lid on an active ferment builds pressure. Both are good lids for the wrong job, and counting them would have put a twelve and a four on this page against products that cannot ferment.
Mouth Size Decides Whether the Count Matters
A count only helps if it matches the jars in your cupboard. Four of these five are for wide mouth jars and one is for regular mouth, and the regular mouth listing is the only one that warns you about the mismatch in writing. Two publish an exact figure for the opening and three describe it in words.
The gallon lid is the sharpest version of the problem. Fermentaholics publishes 110 mm and names standard gallon jars and its own jars, which is a container most households do not already have. Its two lids are the fewest here and each fits by far the biggest jar, and nothing on the listing converts one figure into the other.
Which One Fits Your Kitchen
Six jars running at once with spares in the box. JILLMO supplies six stainless lids, six airlocks and six grommets plus extras, states the fit as 3.38 in and 86 mm for jars from 8 oz to 64 oz, publishes 0.84 lb, and adds a one year replacement for small parts.
Six jars and an airlock you can strip down. Klemon supplies six 18/8 stainless lids with silicone rings and six three piece water airlocks that come apart for cleaning, across jars from 4 oz to 64 oz. Its grommet count is six in the title and nine in the bullet.
Batch work without topping up water. FERMENTER LIDS equips four jars with vacuum seal valves and release tabs rather than water airlocks, plus one oxygen extraction pump shared between them and a date setter on the lid. It publishes 3.62 x 3.62 in and 0.8 lb.
Regular mouth jars you already own. MiniMunch supplies three one piece silicone lids with self burping vents for 70 mm regular mouth jars, and states they are not for 80 mm wide mouth. You supply the metal screw bands, and the listing says so rather than leaving it out.
Two large ferments instead of six small ones. Fermentaholics supplies two 110 mm gallon jar lids, each with a silicone gasket, a rubber grommet and an S airlock, all four stated dishwasher safe. It publishes 0.26 lb and no dimensions for the lid itself.
What We Could Not Verify
These are the things I went looking for in the five listings and did not find.
- Not one of the five says how much finished ferment a jar under its lid actually produces, so the counts cannot be converted into volume.
- Klemon publishes six grommets in its title and nine in its first bullet and does not reconcile them.
- Only one of the five publishes anything about replacing a worn grommet or seal, which is the part that fails first.
- FERMENTER LIDS publishes two dimension figures and no third, and names no material beyond BPA free.
- Fermentaholics publishes no dimensions and no material for the lid, only a weight and a 110 mm fit.
- Three of the five publish no jar size range at all, only that the lid fits a wide mouth or a gallon jar.
