Independent comparisons. We may earn from shop links. More info

Best Forstner bit for the hole you are drilling

Updated: 23 October 2026

You want one sentence that says buy this, and the amazon.co.uk list answers with a 4.8 from six reviews, a £12 set, and an imperial box whose largest bit is 34.9 mm. The best Forstner bit here is the one whose stated diameter matches the fitting, with a review file that is actually about that product. Prices stay on the [Forstner bit comparison](/hub/drilling-and-accessories/forstner-bit). The Products Compared editorial team prepared this page on 20 October 2026 from those listings and named UK pages, without a lab test. A qualifying purchase can earn a commission at no extra cost to you.

You want one sentence that says buy this, and the amazon.co.uk list answers with a 4.8 from six reviews, a £12 set, and an imperial box whose largest bit is 34.9 mm.

Our top picks

IRWIN IRWIN Marples 8-piece Forstner set

Best overall

IRWIN IRWIN Marples 8-piece Forstner set
7.8/10about £57.82
View offer
hsawbit hsawbit 30 mm Forstner bit

Best value

hsawbit hsawbit 30 mm Forstner bit
6.9/10about £9.99
View offer
Aohoo Aohoo 16-piece Forstner set

Rank 3

Aohoo Aohoo 16-piece Forstner set
8.3/10about £15.89
View offer
On this page
  1. 1.Best for a stated 35 mm cup
  2. 2.Best cheap set for occasional holes
  3. 3.Best named set in this basket
  4. 4.What to skip

Best for a stated 35 mm cup

If the hinge sheet says 35 mm, buy a row that prints 35 mm, then set the depth from that sheet. Cup depth is on the 35 mm Forstner bit page. The DTGN two-pack is two tungsten-carbide 35 mm bits at £17.89. amazon.co.uk shows 4.4 from 12 ratings, and several saved texts describe other diameters. The maker's warm tip sends diameters over 35 mm to a drill press, and this bit sits on that threshold. flintronic's six-piece set is £12.39 and lists 10 mm to 35 mm. UK comments say the 35 mm bit is hard to control in 18 mm plywood with a hand drill. Skip IRWIN if the label must say 35 mm. Its largest stated size is 34.9 mm.

Best cheap set for occasional holes

For occasional metric holes up to 35 mm, Aohoo's sixteen-piece set is the top pick on the comparison score: £15.89, from 15 mm to 35 mm, at 4.5 from 2,318 ratings. The table says alloy steel, and the title also says tungsten steel, HSS and titanium coated. Reviewers describe clean holes, then unmarked boxes and bits that dull. flintronic is the cheaper sibling at £12.39. Those conflicts are set out on the Forstner bit set buying guide. The best value line is the hsawbit 30 mm single at £9.99, 4.6 from 287 ratings. Many of those reviews name other diameters. Take it for about 30 mm. Leave it when the job is a hinge.
IRWIN IRWIN Marples 8-piece Forstner set

Testsieger

IRWIN IRWIN Marples 8-piece Forstner set
7.8/10about £57.82
View offer

Best named set in this basket

IRWIN Marples, model 1966892, is the named set. Eight imperial bits run from 6.3 mm (1/4 in) to 34.9 mm (1-3/8 in) at £57.82, with 4.6 from 2,319 ratings. The bullets say a reduced shank for a 3/8 in or larger chuck. Reviewers describe clean cuts and a case that keeps the bits seated. A UK buyer was surprised the steps are imperial, and the material field only says Blend. If the hinge is 35 mm, this is an expensive 34.9 mm bit. If you already work in inches and the chuck is large enough, it is the named set to buy.

What to skip

Skip a star rating when the text names another diameter. YUEDAHOMEE's 41 mm bit is £12.99 and shows 4.8 from six ratings. The saved texts talk about 35 mm and 40 mm bits. The DTGN 90 mm bit shows 4.6 from four ratings, the only saved review is from the United States, and the listing says to use a drill press above 35 mm. Skip Nisorpa and Yueqing Zhongji when the carbide line and the specification table disagree.

Common questions

What is the best Forstner bit if I only need hinge cups?
A bit whose listing states 35 mm, if that is what the hinge sheet says, used with a depth stop. In this basket that is the DTGN 35 mm two-pack when you want carbide and a spare, or a set that includes 35 mm when you want other sizes. IRWIN's 34.9 mm bit is the one to leave. Depth and edge distance stay on the hinge page.
Is a £12 six-piece set good enough for occasional holes?
flintronic at £12.39 is what people use for light plywood and a first 35 mm hole. UK texts also call bits blunt, slow in pine, or about 0.25 mm over size. That is enough for a scrap-tested hinge cup. It is a weak choice if the hole must fit a dowel closely or you are boring hardwood all afternoon.
Which listing should I skip because the reviews are the wrong diameter?
YUEDAHOMEE's 41 mm bit, where the six texts name 35 mm and 40 mm, and the DTGN 90 mm bit, where the only saved text is from the United States. The 30 mm hsawbit and the DTGN 35 mm two-pack also mix other sizes into the sample. Read those as family comments, not as a test of the diameter in the title.
When is a trade carbide bit the better spend?
When you will repeat 35 mm cups in coated board and you want a hinge bit sold for a stand-mounted drill. Faithfull's 35 mm tungsten-carbide bit is £27.61 including VAT. Bosch's EXPERT 35 mm listing on the GB site is £38.36. FAMAG's Bormax geometry starts from £77.45 at one UK seller, and any freehand claim on that geometry stays with that bit.
Can I call any of these a tested winner?
You can call Aohoo the top pick on the published score, and the 30 mm hsawbit the best value on price and review count, and you should say what each award leaves out. Nobody drilled these twelve bits in a lab for this page. A 4.8 from six reviews is not a test result.

Related pages

How to use a Forstner bit

Forstner bit

35mm Forstner bit for a concealed cabinet hinge cup

Forstner bit set: check the diameter and the shank

Forstner bit on a drill press or in the hand drill

Sources

Public UK sources from the research digest, last checked on 20 October 2026. Shelf prices and star lines are the amazon.co.uk figures on the listings.

  1. HSE: wood dust (retrieved 20 October 2026)
  2. PPE at Work Regulations 1992 (retrieved 20 October 2026)
  3. HSE: PUWER overview (retrieved 20 October 2026)
  4. Bosch Professional GB: Forstner bits (retrieved 20 October 2026)
  5. Faithfull: TC 35 mm hinge boring bit (retrieved 20 October 2026)
  6. DIY Doctor: fit a concealed hinge (retrieved 20 October 2026)
  7. Axminster: 16-piece Forstner bit set (retrieved 20 October 2026)
  8. UK Workshop: Forstner bits in hand drills (retrieved 20 October 2026)