If you have ever shopped for a
PDC cutter, you have probably come across codes such as 0804, 1308, 1313 or 1613 and wondered what they actually mean. These four-digit numbers are not random. They are the industry shorthand for the physical dimensions of the cutter, and they directly determine how fast a bit drills, how long it lasts, and which formations it can handle. This guide explains the standard sizes of PDC cutters for drill bits, how the numbering system works, and how to pick the right size for your project.
How PDC Cutter Sizes Are Coded
A PDC cutter, short for polycrystalline diamond compact, is the small disc-shaped cutting element mounted on the face of a
PDC drill bit. Every standard cutter is identified by a four-digit code. The first two digits give the diameter of the cutter in millimetres, and the last two digits give its total height, or thickness, also in millimetres.
For example, a 1308 cutter measures 13 mm across and 8 mm thick. A 1613 cutter is 16 mm in diameter and 13 mm in height. Once you understand this simple rule, reading any cutter specification becomes straightforward, and you can compare products from different suppliers on an equal footing.
The Standard Sizes of PDC Cutters
Although manufacturers produce many variations, the PDC cutter industry has settled on a set of standard sizes that cover most drilling applications. The most common ones are listed below.
| Cutter Size |
Diameter |
Height |
Typical Application |
| 0804 |
8 mm |
4 mm |
Small-diameter bits, soft formations |
| 0808 |
8 mm |
8 mm |
Quarry and stone cutting, small bits |
| 1308 |
13 mm |
8 mm |
Industry benchmark, widest formation range |
| 1313 |
13 mm |
13 mm |
Hard, abrasive formations |
| 1613 |
16 mm |
13 mm |
Medium formations, higher ROP |
| 1616 |
16 mm |
16 mm |
Hard, abrasive formations, maximum durability |
| 1913 |
19 mm |
13 mm |
Soft formations, fastest ROP |
| 1916 |
19 mm |
16 mm |
Soft to medium formations, high ROP |
| 1919 |
19 mm |
19 mm |
Soft formations, large-diameter bits |
Among these, the 1308 cutter is widely regarded as the industry standard because it balances cutting efficiency and durability across the widest range of formations. It is the size most often found in standard water well, mining and geological PDC bits.
What a PDC Cutter Is Made Of
Before choosing a size, it helps to understand the structure of a PDC cutter. Each cutter is made of two layers bonded together under extremely high pressure and temperature. The top layer is polycrystalline diamond, one of the hardest materials known, and it does the actual cutting by shearing through rock. The bottom layer is a tungsten carbide substrate, which gives the cutter toughness and provides a surface that can be brazed onto the bit body.
The height of the cutter matters because it determines the depth of the diamond table. A taller cutter such as a 1313 or 1616 carries more diamond and generally resists abrasive wear longer, while a shorter cutter such as a 1308 stays thermally stable in demanding conditions. The bond between the diamond layer and the carbide substrate is just as important as the size itself, which is why quality control during sintering is critical.
How to Match PDC Cutter Size to Your Formation
The single most important factor when choosing a PDC cutter size is the hardness of the ground you plan to drill. The general rule is simple: harder formations call for smaller cutters, and softer formations allow larger ones.
Hard formations such as granite, hard sandstone and silica-rich rock: choose 1308 or 1313 cutters. Their smaller surface area concentrates the load and resists chipping.
Medium formations such as limestone, shale and interbedded rock: 1613 and 1616 cutters offer a good balance of penetration rate and durability.
Soft formations such as clay, mudstone and soft sandstone: 1913 and 1916 cutters take a bigger bite and deliver the fastest rate of penetration.
Other factors also influence the choice, including the diameter of the bit, the number of blades, the drilling depth and the available torque of your rig. A well-designed bit packs its cutters in a specific pattern, so the cutter size must fit the bit layout without overcrowding or leaving gaps.
Common Mistakes When Selecting PDC Cutters
A few misunderstandings lead to poor buying decisions. First, bigger is not always better. Running large 19 mm cutters in hard rock causes premature chipping and costly downtime, even though the same cutters drill quickly in soft ground. Second, height matters as much as diameter. A thicker diamond table resists abrasion better but can be more brittle under heavy impact, so the two dimensions should be chosen together. Third, the cutter size is only one part of the bit design. Blade count, hydraulic profile and gauge protection are separate engineering decisions that also affect performance.
Where to Source Standard PDC Cutters
When sourcing
PDC cutters for drill bits, look for a supplier that can guarantee consistent dimensions, a pore-free diamond layer and a strong sintered bond. Xi'an Heaven Abundant Mining Equipment Co., Ltd. (TY Drill Bits) is an ISO9001-certified manufacturer based in Xi'an, China, that has specialised in PDC bits, tricone bits, core bits and PDC cutters since 2010. Their PDC cutter range covers the standard sizes used in the industry, including 0804, 0808, 1308, 1313 and 1613, and they also supply PDC cutters for stone cutting and quarry mining applications.
As a manufacturer rather than a pure trader, TY Drill Bits controls the production process from raw material to finished cutter, which makes it easier to keep tolerances tight and quality consistent. The company also offers OEM services and can customise cutters and bits to match specific drilling conditions, with a lead time of around 15 working days.
Frequently Asked Questions
What does 1308 mean in PDC cutter sizing?
It means the cutter has a diameter of 13 mm and a height of 8 mm. The four-digit code always gives diameter first and height second, both in millimetres.
What is the most common PDC cutter size?
The 1308 cutter is the most widely used because it performs well across the broadest range of formations, from soft clay to medium-hard rock.
Can large PDC cutters be used in hard rock?
It is not recommended. Large cutters such as 1913 or 1916 tend to chip and fail under the high impact loads of hard, abrasive formations. Smaller cutters like 1308 or 1313 are a safer choice.
Does a thicker PDC cutter always last longer?
Not necessarily. A thicker diamond table resists abrasive wear better, but it can be more brittle under heavy impact. The right height depends on the formation and the drilling conditions.
Are PDC cutters and PDC drill bits the same thing?
No. PDC cutters are the cutting elements, while a PDC drill bit is the complete tool with cutters mounted on its blades. A bit with 1308 cutters simply means that specific cutter size is installed on it.
Understanding the standard sizes of PDC cutters for drill bits is the first step towards drilling faster and more economically. Match the cutter to your formation, pay attention to both diameter and height, and buy from a manufacturer that can back its products with consistent quality. If you are unsure which size fits your project, a reliable supplier such as TY Drill Bits can recommend the right configuration based on your ground conditions.
Xi'an Heaven Abundant Mining Equipment CO.,LTD
