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

Best diamond drill bit

Updated: 2026-10-23

The best diamond drill bit in a UK search is usually a trade name that is not in this amazon.co.uk sample, or a star rating that mixes a 15-piece wet set with a 6 mm grinder pack. That does not tell you which cutter to put on the machine you already own. A useful pick names the job and names who should skip it. The eleven listings, with prices saved on 19 October 2026, are on the [diamond drill comparison](/hub/drilling-and-accessories/diamond-drill). A 4.5-star line is not a test winner, and a hole count in one review is not a specification. A qualifying purchase can earn a commission at no extra cost to you.

The best diamond drill bit in a UK search is usually a trade name that is not in this amazon.co.uk sample, or a star rating that mixes a 15-piece wet set with a 6 mm grinder pack.

Our top picks

BRSCHNITT BRSCHNITT 32 mm M14

Best overall

BRSCHNITT BRSCHNITT 32 mm M14
9.0/10about £15.79
View offer
DT-DIATOOL DT-DIATOOL five 6 mm M14

Alternative

DT-DIATOOL DT-DIATOOL five 6 mm M14
9.0/10about £24.99
View offer
Meccion Meccion 22 mm pilot saw

Best value

Meccion Meccion 22 mm pilot saw
8.4/10about £9.69
View offer
On this page
  1. 1.Best is a job, not a crown
  2. 2.If you already use an angle grinder
  3. 3.If you need one measured hole with a drill
  4. 4.If the tile costs more than the bit

Best is a job, not a crown

Flintronic’s set is 4.1 from 4,045 reviews, at £10.99, and it is fifteen diamond-coated hole saws from 8 mm to 50 mm for a drill chuck, with water required. DT-DIATOOL is 4.5 from 308 reviews, at £24.99, and it is five 6 mm vacuum-brazed M14 bits. BRSCHNITT is also 4.5, from 1,794 reviews, at £15.79, and it is one 32 mm M14 bit. Those three numbers cannot be lined up as first, second and third. They are different diameters, different machines and different cooling rules. Rubi’s DRYGRES life lines are Rubi’s, and Rubi is not an ASIN here. If you have not yet fixed shank and diameter, the diamond drill buying guide is the page that does that work.

If you already use an angle grinder

If a 115 mm or 125 mm grinder with an M14 spindle is already on the job, stay on the M14 rows. For several 6 mm holes in hard porcelain, DT-DIATOOL at £24.99 is the pack to consider. You get five bits and wax rather than a water requirement. Skip it if you do not own the grinder, or if you need one thick slab hole to be certain. For one 32 mm hole, BRSCHNITT at £15.79 is the top pick in this table, and only for that job. It is vacuum brazed, sold for dry drilling, with water said to prolong life. The shank field says square. The bullets say M14. Fit it as M14. It will not go in a drill chuck. Hex and round shanks do not screw onto M14, and these boxes do not include an adapter.
BRSCHNITT BRSCHNITT 32 mm M14

Testsieger

BRSCHNITT BRSCHNITT 32 mm M14
9.0/10about £15.79
View offer

If you need one measured hole with a drill

If you own a combi drill or a bench drill and the fitting measures 22 mm, Meccion at £9.69 is the sensible single cutter. It is a diamond-coated hole saw with a pilot, and the listing says 500 to 800 rpm with water. UK reviewers describe clean porcelain and ceramic holes when water stays on the rim, and also a saw that lasted one tile and smoke when the water was skipped. That is the best value in this sample for one wet 22 mm hole. Vacuum brazing is not stated. Flintronic at £10.99 is worth a look only when you truly need more than one chuck diameter between 8 mm and 50 mm and you will keep water on every rim. It does not make fifteen pieces the right buy for one measured tap hole. Skip Zeeorymn at £5.99 when the tile is porcelain or you need more than one or two holes.

If the tile costs more than the bit

When the tile is a spare offcut, a £6 or £10 pack is a reasonable experiment, provided the shank matches the chuck and you accept a short life. When the tile is already fixed, glazed, and awkward to replace, spend towards a vacuum-brazed bit of the diameter you measured, on the machine that bit names. In this sample that is the £15.79 to £24.99 M14 rows if you have a grinder, or BGTEC’s ten 6 mm chuck bits at £21.99 if the hole is 6 mm and you will add water. BGTEC reviews include a body that buckled on a dry porcelain slab. Vearter has 13 ratings and YUEDAHOMEE has 18 reviews, so neither carries a pick. Call a fitter when the slab is already fixed, you have no offcut, and the exit is unsupported, or when the material is quartz and you cannot control the dust and slurry.

Common questions

Which listing is the top pick if I already own a grinder and need 6 mm holes?
DT-DIATOOL at £24.99, five vacuum-brazed 6 mm M14 bits, is the pack to consider for several holes. UK reviews include about 20 to 35 holes in hard porcelain and also one and a half holes in 20 mm porcelain, so keep a spare bit in the pack and do not treat either figure as a specification. Skip it if you do not have an M14 spindle.
Which listing is the sensible one-hole 22 mm or 32 mm cutter?
For 22 mm in a drill, Meccion at £9.69, with water and 500 to 800 rpm. For 32 mm on an M14 grinder, BRSCHNITT at £15.79. Skip Meccion if you will not use water. Skip BRSCHNITT if you only have a chuck. Neither listing covers 35 mm or 40 mm, so measure before you assume a near size will do.
Who should skip the £5.99 set?
Skip Zeeorymn if the tile is porcelain, if you need more than one or two holes, or if the only machine is an angle grinder. The set is four wax-filled diamond bits from 6 mm to 10 mm plus a carbide bit, the shank is hex, and no adapter is in the box. UK reviews often describe a diamond layer gone after one or two holes.
Does 4.5 from 1,794 reviews beat 4.5 from 308?
Only if the job is the same. BRSCHNITT’s 1,794 reviews are for a 32 mm M14 bit at £15.79. DT-DIATOOL’s 308 reviews are for five 6 mm M14 bits at £24.99. The larger count supports the 32 mm row as the top pick for that diameter. It does not make a 32 mm bit the right tool for a 6 mm fixing.
Can I name a test winner?
No. These scores follow amazon.co.uk stars. They are not a laboratory test, and none of these bits was inspected against BS EN 13236. Say top pick only for a named job, such as a 32 mm hole on a grinder you already own, and say who should skip that row. A review of another diameter is not evidence for the title in your basket.

Related pages

Drill or angle grinder

Diamond drill for porcelain

Diamond drill

Diamond drill bit buying guide: shank, hole, cooling

How to use a diamond drill bit without burning the rim

Sources

Public UK sources from the research digest, last checked on 19 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file.

  1. Topps Tiles: best drill bits for tiles (retrieved 19 October 2026)
  2. HSE CIS36: dust controls for drilling and coring (retrieved 19 October 2026)
  3. HSE CN8: diamond coring and slurry (retrieved 19 October 2026)
  4. ATS Diamond Tools: diamond drill bit types (retrieved 19 October 2026)
  5. Sigma UK: what size drill bit do I need (retrieved 19 October 2026)
  6. Würth UK: diamond dry core bit for tile, M14 (retrieved 19 October 2026)
  7. HSE: working with engineered stone (retrieved 19 October 2026)
  8. Tiling Supplies Direct: Rubi DRYGRES M14 bits (retrieved 19 October 2026)