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Trapezoid blades made of carbon steel, fanned out
Replacement blades · 97 blades · 13 brands

Cutter knife blades

Replacement blades for cutter, carpet and safety knives – sorted by shape, material, grind and brand.

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K013 Trapezoid blade 53mm | rounded tipsrounded tipsCarbon steelplain, double-bevel€2.90 excl. VATView K013K014 Trapezoid blade 60mm | Premiumvery long blade lifePremium carbon steel, tungsten carbide coatedplain, double-bevel€10.15 excl. VATView K014K015 Trapezoid blades Tajima V-Rex – black, extra sharp (10 pcs.)very high initial sharpnessCarbon steel, black coatedplain, double-bevel€4.04 excl. VATView K015K073 Ceramic safety blade trapezoidCeramic, safety grindCeramicSafety grind€19.99 excl. VATView K073KB1-99 Trapezoid blade 60mm | TiN | 99 hole patternTiNPremium carbon steel, TiN coatedplain, double-bevel€4.35 excl. VATView KB1-99KB1-C Ceramic safety blade trapezoid KB1-CCeramic, safety grindCeramicSafety grind€12.50 excl. VATView KB1-CKB1-S Trapezoid blade 60mm | serrated grindSerrated grindPremium carbon steel€3.99 excl. VATView KB1-SKM99 Trapezoid blade 60mm martor 99universalCarbon steelplain, double-bevel€4.70 excl. VATView KM99KM199 Trapezoid blade 60mm | martor 199 stainlessStainless steelplain, double-bevel€7.32 excl. VATView KM199KM60099 Trapezoid blade 60mm | Martor 60099rounded cornersCarbon steelplain, double-bevel€5.43 excl. VATView KM60099KM160099 Trapezoid blade 60mm | Martor 160099 stainlessStainless steel, rounded cornersStainless steelplain, double-bevel€7.75 excl. VATView KM160099
K011 Trapezoid blade 52mm | universaluniversalPremium carbon steelplain, double-bevel€2.66 excl. VATView K011KB1-E Trapezoid blade 51mm | stainless steelStainless steelplain, double-bevel€5.32 excl. VATView KB1-EKB1-N5 Trapezoid blade 51mm | TiNTiNPremium carbon steel, TiN coatedplain, double-bevel€4.35 excl. VATView KB1-N5KB1-N5R Trapezoid blade 49mm | TiN | roundedTiN, rounded cornersPremium carbon steel, TiN coatedplain, double-bevel€5.32 excl. VATView KB1-N5RKM610 Trapezoid blade 53mm | martor 610 stainlessStainless steelplain, double-bevel€4.68 excl. VATView KM610KM5232 Trapezoid blade 53mm | martor 5232universalPremium carbon steelplain, double-bevel€4.78 excl. VATView KM5232KM5233 Trapezoid blade 53mm | martor 5233single-bevel grindPremium carbon steelplain, single-bevel€4.68 excl. VATView KM5233KM65232 Trapezoid blade 53mm | martor 65232Triple bevelPremium carbon steelplain, double-bevel€5.20 excl. VATView KM65232KM165232 Trapezoid blade 50mm | martor 165232 stainless steel roundedStainless steel, rounded cornersStainless steelplain, double-bevel€8.20 excl. VATView KM165232
K010 Cutter knife blade long for U013 (10 pcs.)extra longCarbon steelplain, double-bevel€3.43 excl. VATView K010K018 Replacement blade for safety knife U003for U003Carbon steelplain, double-bevel€2.04 excl. VATView K018K020 Trapezoid blade | for safety knife UAS100for UAS100Carbon steelplain, double-bevel€7.99 excl. VATView K020K022 Trapezoid blade – stainless for OLFA SKB-2SStainless steel, extra longStainless steelplain, double-bevel€9.85 excl. VATView K022KM60095 Trapezoid blade | Martor 60095short, rounded cornersPremium carbon steelplain, double-bevel€5.40 excl. VATView KM60095
Blade finder

Which blade fits my knife?

Choose a brand or search for a knife – the finder shows all replacement blades that fit the knife. 91 knives from our range are recorded.

Guide to blade knowledge

What matters with cutter knife blades

Whether a blade fits, how good it is and how long it stays sharp – three questions that decide every order. Here are the answers, without advertising promises.

01

Shape and fit

Does the blade fit my handle?

For cutter knife blades there is no standard. Whether a blade fits is decided by three things: the shape, the hole pattern and – less often – the thickness.

The shapes

Trapezoid bladesThe blade for safety and carpet knives. Two corners, turned when one is dull.25 blades →Snap-off blades9, 18 or 25 mm wide. When the tip is dull, a segment is snapped off.18 blades →Polystyrene bladesLong and without predetermined breaking points – for deep cuts in foam and insulation.10 blades →Scalpel bladesFine and pointed – for deburring and precise contours.8 blades →Hook, round and special bladesMostly made for a specific knife – they fit only that handle.36 blades →

The hole pattern

Trapezoid blades look similar – but by no means fit every handle. There is no standard for the hole pattern. The blade carrier holds the blade at notches in the blade back or at large holes in the middle. Exactly these have to match the handle.

about 60 mm

Notches on the back

CountsThe notches at the top of the blade back

Two notches are most common; there are also blades with three or four. Most handles have enough play to take different notches.

about 60 mm

99 hole pattern

CountsTwo large holes in the middle of the blade

Not an official name, but common in the trade – after MARTOR blade no. 99. Handles that hold the blade at these holes take only blades with exactly this hole pattern. Blades no. 99 and no. 199 also have notches on the back and therefore fit many other handles as well; the newer no. 60099 has no notches.

about 52 mm

52 mm blade with centre hole

CountsThe large hole in the middle, plus the notches on the back

Here too there is no standard; the graphic shows the MARTOR blade no. 5232 as an example. The small holes are irrelevant for the fit.

Rule of thumb: What matters is how the knife holds the blade. Knives that fix the blade at the upper notch take most trapezoid blades – US10, U014, UES44, US24 and U005 each fit up to 19 blades from our range. Knives that hold the blade at the holes in the middle, such as many MARTOR and Slice knives, take only blades with the matching hole pattern.

How to check your old blade

  1. 1Length About 60 mm (standard) or about 52 mm? Some handles take only one length, some both.
  2. 2Back How many notches does the blade back have, and where are they?
  3. 3Middle How many large holes does the blade have in the middle? Small holes do not count.

Every product page states under “Fits” which knives the blade is suitable for. If in doubt: send us a photo of the old blade.

The thickness

Thickness is rarely the problem: most blades of one shape are the same thickness and fit everywhere. The exception are ceramic blades – they are often thicker than steel and then do not fit every handle, even if the hole pattern is right.

Snap-off blade 9 mm0.38 mm
Snap-off blade 18 mm0.5 mm
Trapezoid blade (steel)0.6–0.63 mm
Snap-off blade 25 mm0.7 mm
Ceramic trapezoid blade0.65–1.3 mm

Typical values according to manufacturer data sheets (including MARTOR, Stanley, OLFA); individual blades differ. Ceramic: MARTOR 0.65 mm, Slice 0.76 to 1.3 mm.

02

Quality

What makes a good blade

Two blades can look the same and differ clearly in use. Three building blocks make the difference: material, heat treatment and grind. The finish comes on top as a small building block.

1Material

Carbon steel

The standard

+sharp, inexpensive, easy to sharpen

–rusts in moisture

UseCardboard, film, warehouse and shipping

Premium carbon steel

More carbon, higher hardness

+keeps its sharpness longer

–somewhat more expensive

Usewhere a lot is cut every day

Stainless steel

Low-rust from 10.5 % chromium

+corrosion-resistant, with good quality cuts no worse than carbon steel

–basic grades are softer

UseMoisture, food, pharma

Ceramic

Zirconium oxide

+never rusts, non-magnetic, loses its sharpness only slowly (CURT measurement)

–brittle, must not be tilted; often thicker and less sharp at first

UseSafety, food, electronics

“Carbon” or “stainless” alone says little about quality: in test series, good stainless blade steel lasted at least as long as plain carbon steel. What matters is what the manufacturer makes of the steel – hardening and grind. Carbon steel is often named informally after its carbon content: C100 (about 1.0 % carbon) roughly corresponds to Japanese SK5, C125 (about 1.25 %) to SK2. More carbon makes the blade harder and sharper, but also more sensitive to impact.

2Heat treatment

Only heat treatment turns strip steel into a blade. It determines how hard the edge becomes – and whether it stays tough or becomes brittle.

  1. 1

    Hardening

    The steel is heated to over 1,000 °C – only a few seconds for thin blade strip.

  2. 2

    Quenching

    Rapid cooling freezes the hard structure in place. Without protective gas the edge loses carbon and becomes soft.

  3. 3

    Tempering

    Reheating to about 175 to 350 °C removes the brittleness. This is where the compromise is set.

too softdulls quickly, the edge rolls over
righthard and tough at the same time – the edge holds
too brittleThe edge chips, the blade can break

How do you recognise good heat treatment? Reputable manufacturers state hardness and tolerance (e.g. ± 1 HRC). “Specially hardened” without a number is no proof of quality.

YouTube is loaded when playing.

How a blade is made

The video shows the industrial production of razor blades. Cutter knife blades are made on the same principle: strip steel is stamped, hardened and ground.

Video: Xirui Blade Manufacturing (YouTube, in English)

3Grind

In measurements, the grind has the greatest influence on sharpness and blade life. A more acute edge angle cuts more easily – in cardboard even for longer – but is more likely to chip with hard or laterally loaded cuts. High-quality blades therefore often have a multiple grind (two or three facets): fine at the edge, stable behind it.

Grind types on cutter knife blades

The body of a cutter knife blade is the same thickness everywhere – only the facet at the cutting edge is ground. How it is ground decides how the blade moves through the material. The graphics show the blade in cross-section, the magnifier the cutting edge.

plain, double-bevel

Both sides are ground, the edge lies in the middle (V shape). The blade runs straight and is stable at the edge.

UseStandard for trapezoid and snap-off blades – cardboard, film, cutting to size.

plain, single-bevel

Only one side is bevelled, the other stays flat. With the flat side against the workpiece you get very flat, flush cuts.

UseDeburring, trimming protrusions, scalpel and scraper blades.

Side view

Serrated grind

The edge is wavy and ground on one side. The tips bite into the material, in the valleys the blade keeps cutting – it does not slip.

UseTough and fibrous material: rubber, foam, insulation, rope.

Safety grind

The edge does not end in a point but is rounded. It cuts cardboard and film, but is considerably less dangerous to the skin.

UseGoods receipt and order picking, often with ceramic blades.

Schematic, not to scale: a trapezoid blade is about 0.6 mm thick.

+Finish

The colour of a blade says something about its finish – but not automatically that it lasts longer. It depends on what you cut.

FinishWhat it isFilm, thin materialCardboard, abrasive material
Silver (none)Bare steel, no coatinggoodgood – the standard
BlackMainly a finer grind (according to OLFA, Tajima)higher initial sharpnessin our experience no advantage in blade life
CURT experience · OLFA itself recommends the silver blade for cardboard
Gold (TiN)Titanium nitride, only a few µm thin – a nicheintended for filmSpecialist retailers advise against it for cardboard
CURT experience: advantage mainly with film
Tungsten carbideHard metal edge, applied to the steel by lasermore likely to tear thin filmconsiderably longer blade life
According to the manufacturer up to 10 times, method not published · CURT measurement: still not dull after 1,700 cuts, a standard trapezoid blade after about 1,000 (1 blade each – tendency)
03

Sharpness

Initial sharpness is not blade life

“Very sharp” is printed on almost every blade pack. It means two different things – and for work in a business, what counts is usually what is not printed on it.

Initial sharpness

How easily a new blade cuts. It drops from the first cut – most strongly right at the start.

Blade life

How long the blade keeps a minimum sharpness with which you can cut your material without too much force.

Our measurement: how much force does the blade need?

There are no published measurements for cutter knife blades. That is why we measured ourselves: 17 trapezoid blades, each up to 1,700 cuts. The graph shows four of them. The higher the curve, the duller the blade.

051015202505001.0001.500Force in NNumber of cuts →dull from about 18 NABCD
  • A Steel
  • B Steel
  • C Hard metal edge
  • D Ceramic
1

The biggest loss comes immediately

After the first 100 cuts, the steel blades needed two to four times as much force as when new. After that the force kept rising steadily.

2

The sharpest is not the most durable

Blade A started with the lowest force and was dull after about 640 cuts. Blade C needed almost twice the force at first – and was still not dull after 1,700 cuts.

3

Hard edges last longer

Blades with a hard metal edge, bimetal or ceramic were still not dull at the end of the test. Ceramic starts clearly duller but loses only little.

Which blade is better depends on what you cut and how often. Most manufacturers mean initial sharpness by “very sharp” – which says little about blade life.

CURT measurement, as of October 2026. Blade in the handle, guided along a metal rail. Per measuring section cardboard and, in a ratio of 10 : 1, strapping that pulls sideways against the cutting edge. What is measured is the force with which the blade cuts through a nylon thread (0.35 mm), mean of three measurements. One blade was tested per blade type – the values show a tendency, not a laboratory result. Not a standard method, not comparable with ISO 8442-5. Brands are deliberately not named.

What matters more to you?

Initial sharpness counts when …

  • few, precise cuts are needed
  • thin film, paper or wallpaper is cut
  • the blade is changed or snapped off often anyway

Blade life counts when …

  • cutting goes on all day
  • cardboard, strapping or rubber wear the blade down
  • every blade change costs time and money

Only one method for knives is standardised: ISO 8442-5. The blade cuts with a fixed force through a stack of test cardboard containing quartz. The first three strokes give the initial sharpness, the sum of all strokes the blade life. No manufacturer publishes such values for cutter knife blades – factors such as “10 times longer” are manufacturer claims without a method.

Why sharp means safe

The most dangerous blade is a dull blade.

1

Force

A dull edge needs high pressure. More force leads to loss of control – and to slipping.

2

Ergonomics

Sharp blades relieve wrist and tendons, especially in continuous use.

3

Result

Clean cut edges save rework and rejects.

Safety and special blades

Occupational safety starts with the blade, not only with the knife.

Ceramic

Does not rust, is non-magnetic and stays sharp for a long time. Often with a safety grind.

Ceramic safety blades →

Detectable

Blades and knives that metal detectors find – for food and pharmaceutical production.

Detectable products →

Rounded tip

Reduces the risk of stab injuries and protects the contents when opening cartons.

Without snap-off segments

Where no piece of steel may get into the product – for example in the food and automotive industries.

Knives with automatic blade retraction: Safety knives →

Changing and disposing

How to change a blade safely and how to snap off snap-off blades correctly is shown with the cutter knives. Dull blades belong in a collection box at the workplace – not loose in the general waste.

Blade not found?

We work with almost all manufacturers. Send us a photo of your blade or request sample blades to test.

Contact →0211 97174619

Frequently asked questions about blades

Which blade fits my knife?

With snap-off blades the width usually decides – 9, 18 or 25 mm. With trapezoid and special blades the hole pattern and length must match the handle; they are not standardised. Every product page states under “Fits” which knives the blade is suitable for. If in doubt, send us a photo of your blade or call: 0211 97174619.

What does “stainless” mean for a blade?

No blade is truly stainless, only low-rust: from 10.5 % chromium in the steel it counts as corrosion-resistant (DIN EN 10088). Water and acids on the edge then hardly change its properties.

Carbon steel or stainless steel – which is better?

Carbon steel is inexpensive and the usual choice for cardboard, film and most warehouse work. Choose stainless steel where moisture or food is involved. Neither is better or worse across the board – it depends on the steel quality, the hardening and the grind.

How long does a cutter knife blade last?

That depends on the material cut: film hardly stresses the blade, while cardboard with its mineral fillers, strapping and rubber dull it quickly. On the blade side, the grind (edge angle) and the hardness of the steel are what matter most.

What are gold and black blades good for?

Gold blades carry a layer of titanium nitride (TiN) a few thousandths of a millimetre thin. It helps mainly with film and adhesive tape; with cardboard it wears off the edge quickly. Black blades from OLFA and Tajima differ, according to the manufacturers, mainly through a finer grind – they are particularly sharp at first.

Which blades are suitable for food production?

Blades without snap-off segments, so that no piece of steel gets into the product, plus stainless steel or ceramic against rust. Where metal detectors are used, there are detectable knives and blades.

Are ceramic blades worth it?

Ceramic blades cost more than steel blades, but stay sharp considerably longer, do not rust and are non-magnetic. They are worth it where a lot is cut or steel is unwanted. Do not tilt them – ceramic is brittle.

Where to put dull blades?

In a collection box for dull blades, right at the workplace. Loose blades in the general waste endanger waste disposal and belong in the risk assessment.