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Nut splitter set

Updated: 23 October 2026

You have a seized nut and a shortlist of nut splitter sets. The number stamped near the bolt is a thread size. The number that chooses the tool is the distance across the flats. This page is that measurement, the usual bands of 9–12 mm, 12–16 mm, 16–22 mm and sometimes 22–27 mm. Shelf prices saved on 22 October 2026 run from about £10.99 to £25.49. The [Nut splitter comparison](/hub/hand-tools/nut-splitter) holds the nine rows. Peter F. updated this page on 23 October 2026. No lab split. A qualifying amazon.co.uk purchase can earn a commission at no extra cost to you.

You have a seized nut and a shortlist of nut splitter sets. The number stamped near the bolt is a thread size. The number that chooses the tool is the distance across the flats.

Our top picks

BGS BGS 1812 nut splitter set

Best overall

BGS BGS 1812 nut splitter set
7.9/10about £18.11
View offer
Hilka Hilka 12455002 nut splitter

Best value

Hilka Hilka 12455002 nut splitter
7.0/10about £12.56
View offer
QWORK QWORK 3-piece nut splitter set

Alternative

QWORK QWORK 3-piece nut splitter set
7.6/10about £15.45
View offer
On this page
  1. 1.Measure across the flats, not the thread
  2. 2.Two pieces, three pieces, or a single 16–22 mm tool
  3. 3.The hex on the screw, and whether a case matters
  4. 4.What is not a nut splitter

Measure across the flats, not the thread

A splitter marked 12 mm is a frame for a nut whose flats sit in that band. It is not a tool for the thread stamped nearby. A 17 mm nut, common on a standard M10 hex, sits in the 16–22 mm band, not in a body labelled 12–16 mm. A ring that is too small will not pass over, and one that is far too large lets the chisel walk off the flat. Measure the flats you can see. The JEUCLEL title states 16–22 mm, also written as 5/8 inch to 7/8 inch. Buyers who wanted a 1/2 inch nut found the body does not start there. If you do not know the next nut, the set is the point of a nut splitter set.

Two pieces, three pieces, or a single 16–22 mm tool

A two-piece pair covers car and gate sizes without a 9 mm body. BGS 1812 states 12–16 mm and 16–22 mm, at £18.11, with 3.9 from 954 reviews. Hilka 12455002 states 12–15 mm and 16–24 mm, at £12.56, with 3.8 from 68 reviews. Review depth is on the best nut splitter page, not a hardness grade. QWORK adds 9–12 mm beside 12–16 and 16–22 mm, at £15.45 with 3.5 from 707 reviews. The JEUCLEL at £10.99 is only the 16–22 mm body. Four pieces add 22–27 mm. The blue DASBET is £11.39 with 5.0 from one silent review. ZTC0507-1 is £18.99 with 4.0 from 27 reviews. The fourth body is only for a nut already measured above 22 mm.
BGS BGS 1812 nut splitter set

Testsieger

BGS BGS 1812 nut splitter set
7.9/10about £18.11
View offer

The hex on the screw, and whether a case matters

BGS states 14 mm and 19 mm hexes, with lengths of 95 mm and 120 mm. Hilka states the same hexes. JEUCLEL states a 19 mm spanner. QWORK, DASBET, Anhoer and ZYETGH do not state the hex. A case is storage, not a harder chisel. DASBET claims a case. BGS, QWORK and Hilka do not list one. Material words are not a grade. Anhoer says stainless and carbon steel. QWORK says alloy steel and bearing steel. No row states a property class.

What is not a nut splitter

A stud extractor bites a snapped stud. A nut splitter sacrifices the nut and hopes to leave the stud, when the frame can seat on a flat. A tap-head tool is for a tap. Chestnut openers in the same raw batch are kitchen tools and were taken out. The Ejoyous listing at £25.49 also describes twist sockets. Treat it as a mixed box. Wonkee Donkee separates a ring frame from a C-frame, and these nine listings are screw tools, not hydraulic cutters. BGS lengths of 95 mm and 120 mm are the closest figure to whether the body reaches past a flange. Hilka’s package line of 5 × 5 × 5 cm is not a length you can plan with. If the frame will not pass over the nut, more pieces will not help.

Common questions

Is a 12 mm nut splitter the right tool for an M12 nut?
Usually no. M12 is the thread. On a standard hex chart such as RenQuip’s, an M12 nut is about 19 mm across the flats, so it wants a 16–22 mm body, not an opening marked 12 mm. Measure your nut. A flange nut will not match the chart.
Do I need four sizes, or is 9–22 mm enough?
Measure first. A 9–22 mm set covers the three usual bands, which is what QWORK states at £15.45. The fourth body, 22–27 mm, is for a nut you have already found above 22 mm. A single 16–22 mm tool is enough only when every nut in front of you is in that band.
What spanner fits the screw?
Where the listing says so, use that hex. BGS and Hilka state 14 mm and 19 mm. JEUCLEL states a 19 mm spanner. QWORK, DASBET, Anhoer and ZYETGH do not state a hex. Do not assume another brand’s socket will match the screw in the box.
Is a stud extractor the same purchase?
No. A stud extractor grips what is left of a stud. A nut splitter is a chisel in a frame, aimed at the nut, with the hope that the stud survives. If you need a chisel on a nut, buy a listing whose pieces are splitters.
Why are Sealey sets several times the amazon.co.uk price here?
Sealey’s own site lists a two-piece set at £40.74 inc VAT and a four-piece set at £91.14 inc VAT. The amazon.co.uk rows here run from about £10.99 to £25.49. They are not the same catalogue numbers, and a lower shelf price is not a hardness grade. BGS at £18.11 still has reviews that describe a pin breaking.
What can I do if it bends on the first nut?
Stop using that body. A rolled edge or a sheared guide screw is the failure the large review files repeat, often on the first nut. Keep the listing and the photos if the tool never did the job it was sold to do. Section 9 of the Consumer Rights Act 2015 is about satisfactory quality. It does not mean the next size up will succeed.

Related pages

How to use a nut splitter

Nut splitter for seized nuts

Nut splitter

Best nut splitter: the review file, and who to skip

Nut splitter or angle grinder: colder cut or sparks

Sources

Sources from the research digest, last checked on 22 October 2026.

  1. HSE, PUWER overview (retrieved 22.10.2026)
  2. HSE, INDG291 (retrieved 22.10.2026)
  3. Consumer Rights Act 2015, section 9 (retrieved 22.10.2026)
  4. GOV.UK, General Product Safety Regulations 2005 (retrieved 22.10.2026)
  5. GOV.UK, consumer product safety advice for staying safe (retrieved 22.10.2026)
  6. Wonkee Donkee, types of nut splitter (retrieved 22.10.2026)
  7. DIYWiki, threaded fasteners FAQ (retrieved 22.10.2026)
  8. Hilka nut splitter listing, amazon.co.uk (retrieved 22.10.2026)