Best 5/16-Inch Diamond Drill Bits for Tile and Stone
The best 5/16-inch diamond drill bit depends on your material, drill connection, and how many holes you need to make. For a dedicated 5/16-inch option, consider the five-piece set with integrated coolant or a 10-piece set with cooling wax. The BGTEC set also offers ten 5/16-inch bits with a round shank, while the Tavire and five-piece mixed-size sets suit buyers who want multiple diameters. Check shank type and cooling needs before choosing.
| Product | Best for | Key distinction |
|---|---|---|
| 5-Pack 5/16-Inch Core Drill Bits | A dedicated bit size | Integrated coolant and storage case |
| Tavire 6-Piece Set | Several hole sizes | Hex-shank bits in four sizes |
| 5-Pack Mixed-Size Set | Common diameter options | Includes a 5/16-inch bit |
| 10-Piece Green Dry Bits | Multiple same-size bits | Cooling wax; 5/16-inch size |
| BGTEC 10-Piece Set | Repeated 5/16-inch drilling | Round shank and wax core |
5-Pack 5/16-Inch Diamond Core Drill Bits
This set is best for buyers who need several bits in one specific diameter rather than a range of hole sizes. Its listed uses include ceramic, porcelain, marble, granite, tile, stone, glass, and brick. The round shank and integrated coolant are intended for dry drilling, and a storage case is included. Choose it if a uniform 5/16-inch size and built-in cooling are priorities. The listing does not specify a shank diameter, so verify that the bit fits your drill.
Tavire 6-Piece Dry Diamond Drill Bit Set
The Tavire set is best for buyers who need a 5/16-inch bit alongside other common diameters. It includes two each of 1/4-, 5/16-, and 3/8-inch diamond bits, one 1/2-inch bit, and two 1/4-inch Ti and tungsten carbide bits, according to the listing. Hex shanks are described as anti-slip, and vacuum-brazed diamonds are intended to resist heat. Choose this set for size variety and a hex-shank design. It is not a dedicated 5/16-inch pack, so fewer bits in the target size are included.
5-Pack Mixed-Size Diamond Hole Saw Set
This set is best for projects that may require several hole diameters. The listed sizes are 1/4, 5/16, 3/8, and 1/2 inch, also shown as 6, 8, 10, and 12 mm. It is described for ceramic, tile, glass, granite, marble, brick, and stone, with a 1/4-inch hex shank. Choose it if flexibility is more important than having several 5/16-inch bits. The listing does not detail a cooling method, so check the product instructions before drilling.
10-Piece 5/16-Inch Green Dry Diamond Bits
This set is best for buyers who want a larger number of same-size bits for tile and hard-material jobs. The listing specifies ten 5/16-inch, 8 mm hex-shank bits with cooling wax and brazed diamond construction. It names porcelain tile, ceramic, concrete, granite, marble, and other hard materials as intended uses. Choose it when quantity and the hex connection match your needs. Avoid it for wood; the listing explicitly says it is not for wood.
BGTEC 10-Piece 5/16-Inch Diamond Bit Set
The BGTEC set is best for repeated 5/16-inch holes when a round-shank bit is preferred. Each listed bit is 8 mm in diameter with an 8 mm diamond length. The listing names granite, marble, masonry, concrete, tile, ceramic, glass, and hard plastic as applications. Built-in wax is described for cooling and lubrication, and side openings are intended to help remove stone chips. Confirm that the round shank suits your drill, and follow the maker’s drilling guidance for the material.
Buying Guide: How to Choose a 5/16-Inch Diamond Drill Bit
Do you need one size or several?
A dedicated 5/16-inch set is the straightforward choice when every hole must be the same diameter. The five-piece and two 10-piece sets focus on that size. Mixed-size sets are better for varied projects, but their total bit count does not mean every bit is 5/16 inch. Check how many bits are supplied in the target size.
Which shank type fits your drill?
These options include round and hex shanks. Confirm the drill’s chuck and the bit’s shank dimensions before purchase. The mixed-size five-piece set lists a 1/4-inch hex shank; the Tavire set uses hex shanks, while the first and BGTEC sets specify round shanks. Do not assume shank types are interchangeable for your setup.
What does dry drilling mean for cooling?
Several products describe built-in coolant or wax, but cooling details differ by set. The first set lists integrated coolant; the green dry set and BGTEC set list cooling wax. Check instructions for the material and bit, and do not assume “dry” means the bit can be used without following cooling directions.
How should the material affect your choice?
Compare the listed applications with the surface you plan to drill. Porcelain, ceramic, glass, granite, and marble appear across multiple listings, while the green set also names concrete and explicitly excludes wood. Select a bit intended for your material, use appropriate eye protection, and avoid forcing the bit through the workpiece.
Frequently Asked Questions
Is 5/16 inch the same as 8 mm?
They are close, but not exactly the same measurement: 5/16 inch is approximately 7.94 mm. Several product listings describe the size as 8 mm or both 5/16 inch and 8 mm.
Can a 5/16-inch diamond bit drill porcelain tile?
Several listed sets specify porcelain or ceramic tile as an intended material. Confirm that the product’s instructions cover your tile and use the recommended drilling technique.
Do all these sets include only 5/16-inch bits?
No. The first, green, and BGTEC sets are listed as 5/16-inch sets. The Tavire and other five-piece sets include multiple sizes.
Should I choose a hex or round shank?
Choose the shank that matches your drill chuck and setup. The product listings identify the shank styles, but do not assume compatibility without checking your drill’s specifications.