The best diamond drills, compared.
Top pick: BRSCHNITT 32 mm M14 – Highest star score in the set, 4.5 from 1,794, ahead of the other 4.5 line on review count, for one 32 mm vacuum-brazed M14 hole. Best value: Meccion 22 mm pilot saw – One 22 mm saw at about £9.69 with a stated 500 to 800 rpm and water, and 4.2 from 815 reviews, rather than the cheapest pack. Updated October 2026.
A diamond drill is a hole cutter that grinds a round opening through tile, porcelain, glass or stone. It is not a masonry bit or a rotary burr. In a UK bathroom or kitchen you buy one when a fitting needs a measured hole and a twist bit would skate or glaze the surface. You tell a suitable diamond drill by checks that stay true when models change. The shank has to match the machine: an M14 thread for a typical 115 mm or 125 mm angle grinder, or a hex, round or triangular shank for a drill chuck. An adapter bought later does not turn a high-speed grinder bit into a low-speed drill bit. The diameter has to match the fitting. The bond and the cooling plan have to match the material. A coated pilot saw is usually a wet, slow chuck job. A vacuum-brazed rim is the usual dry-porcelain claim, often with wax in smaller diameters. Wax cools the rim. It is not dust control. Those checks are set out in the [diamond drill buying guide](/hub/drilling-and-accessories/diamond-drill/sub/diamond-drill-buying-guide).
A diamond drill is a hole cutter that grinds a round opening through tile, porcelain, glass or stone. It is not a masonry bit or a rotary burr.
38 products checked · 58 hrs invested · +18,600 readers
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Personal buying guide
Question 1 of 2
Which machine will drive the bit?
The BRSCHNITT bit is a single 32 mm vacuum-brazed cutter with a 10 mm diamond height and a 60 mm length, at £15.79, for an M14 angle grinder. Across 1,794 amazon.co.uk reviews the line is 4.5, tied on stars with the DT-DIATOOL five-pack and ahead of it on review count, which is why this row is the top pick for a measured 32 mm hole on a grinder you already own. UK reviewers report a clean tap or shower hole in ceramic, a fast quartz splashback when the rim is started at an angle, and about 10 holes in 20 mm porcelain, which one buyer called fair for the price. The listing sells it for dry drilling and says water can prolong life. Short life on a longer run of 20 mm porcelain is the repeated limit, and the rim skates if you present it upright. The shank field says square while the bullets say M14, so fit it as M14. It does not go in a drill chuck, and a UK review says it will not fit a standard hole-saw arbour.
Pros
Cons
Best for: You already own an M14 grinder and need one 32 mm hole in tile, with water if you want more life.
Less suitable: You only have a drill chuck, or you need dozens of holes in 20 mm porcelain from one bit.
Specifications
Common questions
Is the shank square or M14?
The shank field says square. The bullets and the grinder line say M14. Use M14.
Does it need water?
The listing sells it for dry drilling and says water can prolong life.
DT-DIATOOL sells five 6 mm vacuum-brazed M14 bits with wax inside, a 10 mm diamond height, a 62 mm length and grit #40/50, at £24.99. Across 308 amazon.co.uk reviews the line is 4.5, the same star line as the BRSCHNITT 32 mm bit and a smaller count, so this pack is not the top pick on review volume. UK reviews include about 20 to 35 holes in hard porcelain from one bit, a dry quartz cut with pauses while the wax cooled the rim, and a run of porcelain floor holes on an angle grinder. The same listing also has a UK review of one and a half holes in 20 mm porcelain before the bit stopped, and another of about 10 holes. The core can be cleared from the head, which reviewers mention as a practical point. Water is not required on the listing. Those life reports disagree too widely to treat any one of them as a specification.
Pros
Cons
Best for: You already run an M14 grinder and expect several 6 mm holes in hard porcelain, with a spare bit in the pack.
Less suitable: You need one 20 mm slab hole to be certain, a chuck fit, or the lowest price in the table.
Specifications
Common questions
Does this set need water?
The listing sells it for dry drilling and says the wax helps cooling. It does not require water.
What machine does the listing name?
An M14 thread for an angle grinder.
BGTEC sells ten 6 mm round-shank bits at £21.99, vacuum brazed, with wax inside and a stated diamond length of 10 mm. Across 1,582 amazon.co.uk reviews the line is 4.4. The listing allows dry drilling and says water gives a longer life. UK reviewers used the bits on hard bathroom tile after ordinary tile bits had failed, and some report about 10 to 20 holes in porcelain. In one review, water cooling lifted life from one hole to three or four. Cores jam inside the bit, with no easy way to clear them, and the body buckled when a porcelain slab was drilled dry. Some bits last a single hole. The surface-recommendation field names ceramic, glass and plastic, while the bullets also list granite, marble, masonry, concrete and tile, and an M14 thread is not stated.
Pros
Cons
Best for: You want a stock of 6 mm chuck bits for bathroom tile and you will add water on porcelain.
Less suitable: You need an angle-grinder thread, a dry slab without buckling risk, or an easy way to knock the core out.
Specifications
Common questions
Does the listing allow dry use?
Yes. It also says use water for a longer time.
What shank is it?
Round shank, for a drill chuck. An M14 thread is not stated.
SHDIATOOL sells two 6 mm wax-filled vacuum-brazed bits on an M14 thread, at £15.99, with 6,000 rpm recommended and 11,000 rpm as the stated maximum. Across 770 amazon.co.uk reviews the line is 4.4. The title says two bits and the number-of-pieces field says 20, so count the two in the title. UK reviewers report porcelain bathroom holes, including one account of 13 holes with life still on the bit, and a faster cut than earlier chuck-drill diamond bits. Clean edges show up when the cut stays slow and water is added, although the listing does not require water. In one review both tips burnt off after about 10 holes, and the cut often drops off after a strong start. Leaning on 10 mm porcelain leaves a rough edge, and a drill needs an adapter that is not in the box.
Pros
Cons
Best for: You have an M14 grinder and a short run of 6 mm porcelain holes, and you will keep to the stated speed.
Less suitable: You need a chuck fit without buying an adapter, or a diameter other than 6 mm.
Specifications
Common questions
How many bits are included?
The title and the set name say two 6 mm bits. The number-of-pieces field says 20.
What speed does the listing state?
6,000 rpm recommended and 11,000 rpm maximum.
Can it go in a drill?
Only with an adapter. The listing names SDS Plus, hex or round adapters and does not include one.
The DKIBBITH pack is wax-filled bits at 5 mm, 6 mm, 6 mm, 8 mm, 10 mm and 12 mm, plus a 6 mm masonry bit and a stated heavy-duty case, at £12.99. The listing says the bond is vacuum brazed and that you should let the bit cool after each hole. Across 414 amazon.co.uk reviews the line is 4.3. UK reviewers report hard ceramic and porcelain holes when water is used, and they like having several diameters in one case for less than a single trade-counter bit. Wear after about 6 to 12 holes in hard tile or marble is a common limit, and granite results are mixed. One buyer could not drill a thick stone slab and later said that expectation was wrong. The bullets name angle grinders, but no adapter is in the box, and the masonry bit is not a diamond bit.
Pros
Cons
Best for: You want several small chuck diameters in a case for ceramic and thin porcelain, and you will pause between holes.
Less suitable: You need an M14 fit, a thick stone slab, or a masonry bit to cut the tile itself.
Specifications
Common questions
Is the masonry bit a diamond bit?
No. The box is six diamond sizes plus one 6 mm masonry bit.
Does the listing include a case?
Yes. The bullets say a heavy-duty case.
The Zeeorymn set gives you four wax-filled diamond bits at 6 mm, 6 mm, 8 mm and 10 mm, plus a separate 6 mm carbide bit, for £5.99. Across 74 amazon.co.uk reviews the line is 4.3. UK reviewers who stayed on ceramics and kept the bits cool report a few home holes, and the bits arrived in individual containers. The same reviews often say the diamond layer is gone after one or two holes, even when cooling fluid was used, and more than one buyer says the set will not cut porcelain. The bullets name drills, angle grinders and bench drills, but no adapter is listed, so the hex shank belongs in a chuck. The carbide piece is a different tool from the diamond rims. The listing does not confirm a case, and a flimsy bag comes up in the reviews.
Pros
Cons
Best for: You need a few small ceramic holes in a drill chuck and can treat £5.99 as a short-life pack.
Less suitable: You are drilling porcelain, fitting an M14 grinder, or expecting more than one or two holes.
Specifications
Common questions
Does this set need water?
The listing sells the diamond bits as dry, with wax inside. It does not say water is required.
Will the hex shank screw onto an angle grinder?
The bullets name drills, angle grinders and bench drills. No adapter is listed in the box.
Is the carbide bit a diamond bit?
No. The set is four diamond bits plus one 6 mm carbide bit.
The Meccion hole saw is one 22 mm diamond-coated cutter with a removable pilot, at £9.69, and the listing tells you to stay at 500 to 800 rpm with water. Across 815 amazon.co.uk reviews the line is 4.2, which is why it carries the best-value mark in this sample: one measured diameter, a stated speed, and a large review count, rather than the cheapest pack. UK reviewers describe clean holes in porcelain and ceramic when water stays on the rim, and the pilot is praised for the start. The same sample includes a bit that lasted one tile, cracked tiles when the cut was forced, and a pilot that wandered or drilled slowly. Smoke appears when water is skipped. Reviews that name 20 mm or 95 mm are not this 22 mm title, so those diameters are not evidence for this saw. The body is carbon steel, and vacuum brazing is not stated.
Pros
Cons
Best for: You need one 22 mm hole in a drill chuck and you will keep water on the rim.
Less suitable: You need a dry cut, an M14 grinder fit, or a long run of holes from one saw.
Specifications
Common questions
Does this hole saw need water?
Yes. The listing says keep the speed at 500 to 800 rpm and use water.
Can the pilot come out?
Yes. The listing says remove the centring bit once a round slot is drilled.
ColumPRO sells five 6 mm hex bits with wax at the front and back, at £9.49, and the listing says water is not required. Across 184 amazon.co.uk reviews the line is 4.2. The title and the piece count say five bits, while the unit-count field says 6. UK reviewers report porcelain holes when speed and pressure are eased, and one bit is said to have managed about 20 holes in 8 mm ceramic with a spray bottle. Other buyers used the whole box for two holes, and wax coming out on first use is a repeated complaint. Every bit is the same 6 mm, which one reviewer had not expected from the advert. Glass broke in one review, so this pack is a poor choice if the pane cannot be replaced.
Pros
Cons
Best for: You already know you need several 6 mm holes in a chuck and will keep the speed down.
Less suitable: You need more than one diameter, a guaranteed porcelain run, or a glass pane you cannot replace.
Specifications
Common questions
How many bits are in the box?
The title and the piece count say five 6 mm bits. The unit-count field says 6.
Does the listing require water?
No. It says the wax is for dry drilling and that water cooling is not required.
The YUEDAHOMEE saw is one 65 mm vacuum-brazed hole cutter with a pilot, a triangular shank and a stated cutting depth of 30 mm, at £16.99. Across 18 amazon.co.uk reviews the line is 4.2, and only 12 of the reviews read for this pass were UK reviews, so the sample is thin. The bullets sell dry drilling and list porcelain, ceramic, granite, marble and masonry, while the compatible-material field says glass only. UK reviewers describe a neat hole in solid floor tile and a pilot start for a basin waste in porcelain wall tile, in a standard drill. The second hole failed in one review, and the pilot snapped on the second hole in another. Several reviews describe 60 mm, 32 mm or 50 mm, which are not this title. An angle grinder is not stated.
Pros
Cons
Best for: You need one 65 mm hole in a drill, you have checked the title diameter, and you can spare a second attempt.
Less suitable: You need a large review sample, an M14 grinder, or a listing whose material field matches the bullets.
Specifications
Common questions
What diameter is the title?
65 mm, with a stated cutting depth of 30 mm.
Which material does the table name?
The compatible-material field says glass. The bullets also list porcelain, ceramic, granite, marble and masonry.
The Flintronic set is fifteen diamond-coated hole cutters from 8 mm to 50 mm for a drill chuck, at £10.99, and the listing says water is required. Across 4,045 amazon.co.uk reviews the line is 4.1, the largest count in this sample and also the lowest star line. UK reviewers cut tile when water stayed on the bit and the start was angled, including a reported 40 mm porcelain hole at a slow speed. The price is low if you compare it with one trade cutter per diameter, though you still pay for sizes you may never use. The pilot is often called useless or wandering, and the rim burns out without a constant spray. Several buyers report only a few holes before the cutter is finished, and some tiles are not cut at all. Vacuum brazing is not stated, and the set is not an M14 fit.
Pros
Cons
Best for: You want several chuck diameters for occasional wet tile holes and will keep a spray on the rim.
Less suitable: You need one measured hole, a dry vacuum-brazed bit, or an angle-grinder spindle.
Specifications
Common questions
Does this set need water?
Yes. The listing says water lubrication is required when drilling hard materials.
Does it fit an angle grinder?
The compatible-devices line is an electric drill with a suitable chuck, not an M14 spindle.
The Vearter bit is one hex step cutter at 20 mm, 35 mm and 50 mm, at £18.89, with vacuum brazing stated and dry or wet use on the listing. Across 13 amazon.co.uk reviews the line is 4.0, and only three UK reviews were in the sample read for this pass. Those reviews confirm the three diameters and say the hex shank did not slip in the chuck. One UK review puts each step at about 12 mm high, which is a review measurement rather than a spec field, and says it does not work like a metal step drill. Another review simply calls the quality poor. The title mentions an angle grinder, but the spec shank is hex and no M14 thread is in the spec block. Treat 13 ratings as a thin sample, not a life test.
Pros
Cons
Best for: You want 20 mm, 35 mm and 50 mm on one hex shank and you accept a very small review sample.
Less suitable: You need an M14 thread, a deep cut at each step, or a life figure you can trust.
Specifications
Common questions
Does it need water?
The usage line says dry or wet.
Is the shank M14?
The spec shank is hex. The title mentions an angle grinder. No M14 thread is in the spec block.
Eleven diamond drills on amazon.co.uk were scored on 19 October 2026. The 0–100 score on each row is the listing’s star rating times 20. It was not recalculated from a lab test, a hole count, or a certificate to BS EN 13236. The top pick is the higher review count where two rows share 4.5. The best value is one stated diameter with a stated speed and water, not the lowest shelf price. The weights below are the order used to read a listing. They do not change the star score.
Machine and shank
30%M14 screws onto a typical UK 115 mm or 125 mm angle grinder. Hex, round and triangular shanks go in a drill chuck. An adapter is not in these boxes, and it would not turn a grinder bit into a drill bit.
Diameter
25%The fitting is measured first. Typical tap holes are 22 mm, 32 mm, 35 mm and 40 mm. Fixings are often 6 mm to 12 mm. A wide set is a poor match for one measured hole.
Bond and cooling
25%Vacuum-brazed is the usual dry-porcelain claim, often with wax in small diameters. A coated pilot saw usually wants water and a slow drill. Wax cools the rim. It is not dust control.
Life notes
20%UK reviews are read against the tile, not as a specification. A hole count in one review is not copied onto the row as a rated life. Packs under about £11 draw more short-life comments.
Start with the machine and the shank, then the diameter, then the bond and the cooling. A star rating comes after those checks. The notes below follow that order for these eleven amazon.co.uk listings, checked on 19 October 2026. None of the scores is a drilling test.
A diamond drill is a hole cutter that grinds a round hole through tile, porcelain, glass or stone. It is not a masonry bit and it is not a rotary burr. UK buyers are usually in a bathroom or kitchen, cutting for a tap, a waste or a fixing. You judge the cutter by shank, diameter, bond and cooling. An amazon.co.uk star rating does not rank those jobs against each other. The shank has to match the machine you already own. An M14 thread screws onto a typical UK 115 mm or 125 mm angle grinder.
A 15-piece wet set still has to be cooled, and you pay for diameters you may never use. Measure the fitting first. Typical tap holes are 22 mm, 32 mm, 35 mm and 40 mm.
A hex, round or triangular shank goes in a drill chuck. None of these boxes includes an adapter. A bullet that names an angle grinder does not put a thread in the box.
UK reviews on one listing run from about one hole to a few dozen. The same product can contain both. Wax is not dust control, and a water-fed saw run dry is linked to a burnt rim.
Match the machine before the brand. An M14 thread fits a typical UK 115 mm or 125 mm angle grinder. A hex, round or triangular shank fits a drill chuck. An adapter does not turn a high-speed grinder bit into a low-speed drill bit. Larger holes are the usual M14 job. Dry grinder bits are sold near 11,000 rpm, and up to 14,000 rpm. Chuck saws are slower. Meccion states 500 to 800 rpm with water. SHDIATOOL states 6,000 rpm recommended and 11,000 rpm maximum. Then measure the fitting.
Electroplated bits are one nickel-held layer, usually wet and slow in a drill. Vacuum-brazed bits are the usual dry-porcelain claim, often wax-filled in small diameters. Sintered bits are the longer-life trade construction. None of these eleven listings is a named sintered trade bit. Wax cools the rim. It is not dust control. HSE CIS36 says pre-wetting is not water suppression. At work, dry coring needs suitable extraction, and slurry must not dry out.
Three typical situations, each with a recommendation from this comparison.
You want one cutter in a known diameter and a cooling plan you can follow. The Meccion 22 mm hole saw is about £9.69, with a stated 500 to 800 rpm and water, and 4.2 from 815 reviews. It is the best value in this set for that single wet hole.
You already run an M14 grinder and expect several holes in hard porcelain. The DT-DIATOOL pack is five 6 mm vacuum-brazed bits at about £24.99, with 4.5 from 308 reviews. Life reports on that listing disagree, so keep a spare bit rather than treating one review as a specification.
Quartz and other engineered stone need water or extraction and proper respiratory protection, or a stone fitter. Wax-filled dry cutting is not that control. If the hole is still one wet chuck cut, the Meccion 22 mm saw is the row that states water. If you cannot control the dust and the slurry, do not start.
In this set of eleven amazon.co.uk listings, checked on 19 October 2026, the top pick is the BRSCHNITT 32 mm M14 bit at about £15.79, with 4.5 from 1,794 reviews. The DT-DIATOOL five-pack of 6 mm bits shares the 4.5 line from 308 reviews, and the larger review count decides the tie. The best value is the Meccion 22 mm hole saw at about £9.69, with 4.2 from 815 reviews: one stated diameter, a stated 500 to 800 rpm, and water. Zeeorymn is cheaper at about £5.99, and UK reviews on that pack often stop at one or two holes. Neither mark is a laboratory result or a certificate to BS EN 13236.
BRSCHNITT 32 mm M14
Highest star score in the set, 4.5 from 1,794, ahead of the other 4.5 line on review count, for one 32 mm vacuum-brazed M14 hole.
Meccion 22 mm pilot saw
One 22 mm saw at about £9.69 with a stated 500 to 800 rpm and water, and 4.2 from 815 reviews, rather than the cheapest pack.
Editorial
Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Guides on what to look for, how to use a product, and common mistakes.
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.
Expert source (DIY & tools): Charlie White (Charlie DIYte) (external profile) – public expert commentary used as a research source, not as a contributor to our pages.
This page contains affiliate links to amazon.co.uk. If you buy through them, we may earn a commission at no extra cost to you. Prices, stars and review counts are from the UK listings checked on 19 October 2026. We did not lab-test these diamond drills.
