What Is a Petty Knife? Japan's Small Utility Blade
A petty knife is a small, thin, pointed Japanese knife for the jobs that fall between a paring knife and a chef’s knife. The name comes from the French petit. If you have ever reached for your big knife to slice a single shallot and found it unwieldy, or picked up a paring knife to trim a chicken thigh and found it too small, a petty is the knife you were missing. This guide covers what it does, how it differs from a paring and a utility knife, and what size to buy.
What a petty knife is
A petty is a scaled-down all-rounder. It has the same double-bevelled, pointed, gently curved shape as a gyuto, just shorter, usually 120 to 150mm, and ground thin for precise work. It is at home both in your hand, the way you would use a paring knife, and on a board, the way you would use a chef’s knife on a small scale.
That dual role is the point. A paring knife is really an in-hand tool and awkward on a board. A chef’s knife is a board tool and clumsy for anything small. A petty does both jobs passably and neither perfectly, which turns out to be exactly what a home kitchen needs alongside one bigger knife.
Petty shapes vary more than you might expect. Some are almost straight, closer to a small slicer, and suit clean push cuts. Others have a pronounced curve like a miniature gyuto and take a rocking motion. Neither is wrong; a gently curved 150mm petty is the most generally useful, since it can do a bit of both.
Petty vs paring vs utility knife
The three overlap, and the names get used loosely, but there are real differences.
- Paring knife. Around 90mm, often with a straight or slightly curved edge, built for in-hand work: peeling, coring, hulling strawberries, segmenting citrus. Too short and too curved to be useful on a board.
- Western utility knife. Around 130mm, thicker, sometimes part-serrated, a jack-of-all-trades that does most things adequately and nothing sharply.
- Petty. 120 to 150mm, thin behind the edge, keen, with a flatter profile than a paring knife and a proper point. It does the paring knife’s in-hand jobs, plus real board work, plus fine trimming, and it holds a much sharper edge than a typical utility knife.
Our petty versus paring versus utility knife guide works through all three in full, but in short: a petty is a paring knife you can also chop with, or a utility knife that actually cuts.
What a petty is good for
The common thread is small scale and precision. Anything where a full-size blade feels like too much knife, or where you want to work in your hand rather than on a board, is petty territory. It is also the knife you reach for when the big one is already dirty and you just need to halve a lemon.
In your hand:
- Peeling and coring fruit and vegetables
- Hulling strawberries, segmenting oranges, prepping a mango
- Deveining prawns
- Cutting cheese and fruit at the table
On a small board:
- A shallot, a couple of cloves of garlic, a thumb of ginger, a handful of herbs
- Small amounts of anything when getting the big knife out is overkill
- Slicing a tomato or a small onion
Fine work:
- Trimming fat and silverskin off meat
- Portioning a boneless chicken thigh
- Detail cuts where a long blade is in the way
The two-knife kitchen
For most home cooks, a santoku or a gyuto plus a petty covers around ninety per cent of everything. The big knife does the volume work: onions by the pound, squash, cabbage, carving. The petty picks up everything small and fiddly the big knife is bad at. Add a serrated bread knife, which does not need to be Japanese, and you have a complete kitchen for a fraction of what a block set costs.
If you cook for one or two people, the split shifts further toward the petty. Small portions, a single serving of vegetables, half an onion: much of that is more comfortable on a 150mm blade than a 210mm one, and the big knife comes out mainly for the occasional larger job.
If you are still choosing your first knife, our guide to choosing a first Japanese knife covers that. The petty is the knife to add second.
Why not just keep a paring knife?
You can, and many kitchens do. But a paring knife stops at the edge of the sink: it is too short and too curved to prep a shallot on a board, so you end up reaching for the big knife anyway. A petty absorbs both roles, which means one fewer knife to sharpen and store, and it holds a far sharper edge than a supermarket paring knife. If you already own a paring knife you like, a 150mm petty still adds the board work it cannot do.
120mm or 150mm?
- 120mm. More of an in-hand knife. It excels at paring tasks and detail work and is easy to control, but it is short for board work.
- 150mm. The more versatile choice for most people. Long enough to be a genuine small chef’s knife on a board, still short enough for in-hand use, and the better single petty if you are only buying one.
If you already own a very short paring knife and want the petty for board work, go 150mm. If you want a nimble detail knife and have a chef’s knife for everything else, 120mm is fine.
What to look for
A petty gets used casually. It gets left on the board mid-prep and grabbed for a quick job, so stainless steel matters more here than on a knife you treat carefully. VG-10, Ginsan, and easy-care stainless steels are the right call. A carbon steel petty is possible but the constant small uses make its maintenance a chore; our carbon versus stainless guide explains why.
Look for a proper pointed tip. Some pettys are stubby, which kills their usefulness for trimming and detail work. And look for a thin blade: a petty that is thick behind the edge loses the precision that is the whole reason to own one. Blade thickness or weight on the spec sheet tells you more than the steel name.
On hardness, around 58 to 61 HRC is forgiving and easy to sharpen. Very hard steels matter less on a petty than on a big knife, because you are not putting it through hours of continuous work, and a softer edge is easier to touch up for the quick jobs a petty does.
On the handle, a wa-handle is light and blade-forward, which suits a small knife well; a Western handle is heavier and more familiar. On a knife this size the difference is small, so buy on price and looks if you cannot handle both.
Chubo Inox Petty 150mm
USD 99 (checked Sep 8, 2026)
- Hand-finished in Seki, an easy-care stainless steel for everyday use
- Thin blade profile — about 1.7mm at the spine tapering to 0.5mm at the tip — for light, precise cuts
- Simple to maintain, a good fit for cooks new to Japanese knives
Frequently asked questions
Petty or paring knife?
A petty if you want one knife for both in-hand jobs and small board work. A paring knife only if you specifically want a short, in-hand tool for peeling and coring and you already have something for the board.
What size petty knife should I get?
150mm for most people. It works both in the hand and on a small board. Choose 120mm only if you want a dedicated detail and paring knife and have a chef's knife for everything larger.
Do I need a petty knife?
If you own one all-rounder and often find it clumsy for small jobs like a single shallot or trimming meat, yes. A petty is the knife that makes a two-knife kitchen feel complete.
Can a petty knife replace a chef's knife?
No. A 150mm petty can do a surprising amount, but it is too short and too light for volume prep, large vegetables, or carving. It is a companion to a bigger knife, not a substitute.
The short version
A petty is the small Japanese utility knife that handles everything your big knife is too clumsy for and your paring knife is too small for. Paired with a santoku or a gyuto, it makes a complete home kitchen. For your first one, get a thin, pointed, stainless blade at 150mm, around 58 to 61 HRC, and buy it once you have the all-rounder it is meant to sit beside.