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The Best Calibration Surface Plates

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Our picks are based on Amazon bestseller rankings, verified customer ratings, and product availability. We update our recommendations regularly to ensure accuracy.

Achieving precise measurements is crucial in many fields, from manufacturing to scientific research. A calibration surface plate provides a stable and accurate reference plane for these tasks. Selecting the right one ensures the integrity of your work and the reliability of your results.

SaleNo. 1
HHIP 4401-1597 6" X 8" X 2" Granite Surface Plate, Grade B, 0 Ledge
  • The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001". It is a Grade B (Grade 1) plate.
  • Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
  • Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
  • They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive.
  • Surface plates are offered by HHIP in various sizes, with different levels of flatness and accuracy and are checked by an auto collimator for overall accuracy assurance.
No. 2
Woodriver Granite Surface Plate 12" X 18" X 3" A Grade
  • Stable, ultra flat surface
  • Flat to .00005
  • Moisture and corrosion free
  • Easy to clean -
  • WoodRiver is proudly made by Woodcraft, America’s leading supplier of high-quality woodworking hand tools, power tools, domestic and exotic wood, shop supplies, project plans and kits, plus so much more! Offering first-rate products for all your...
No. 3
HHIP 4401-1596 6" X 6" X 2" Granite Surface Plate, Grade B, 0 Ledge
  • The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-0001". It is a Grade B (Grade 1) plate.
  • Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
  • Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
  • They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive.
  • Surface plates are offered by HHIP in various sizes, with different levels of flatness and accuracy and are checked by an auto collimator for overall accuracy assurance.
No. 4
TTC 9" x 12" x 2" Thick Grade B No Ledge Granite Surface Plate
  • For general inspection work throughout the shop.
  • Meets or exceeds Federal Specification GGG-P-463C.
  • Harder than steel.
  • Retains accuracy for years.
  • Overall accuracy: ±.0003"
No. 5
LLDSIMEX 12 Inch Length 9 Inch Width 3 Inch Thickness Granite Surface Plate, No Ledge 12x9x3 Inch
  • Tool Room Grade "B" Granite Plates
  • Bilateral Accuracy of Plus or Minus 0.0001"
  • Practically Maintenance Free and Won't Corrode Like Steel
  • For General Inspection Work Throughout The Shop
No. 6
Dasqua 8500-4040 Grade A Granite Surface Plate, 400 x 400 x 60 mm Size
  • The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001"; It is a Grade A (Grade 0) plate
  • Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection (Note that these are not NIST traceable)
  • Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage
  • They are also used as a work surface for assembling, inspecting, and marking parts; Non-magnetic and non-conductive; Harder than steel and does not nick or burr
  • Surface plates are offered by HHIP in various sizes and brands, with different levels of flatness and accuracy and are checked by an auto collimator for overall accuracy assurance
No. 7
Dasqua 8500-0017 Grade A Granite Surface Plate for Precision Measurement, 300 x 200 x 60 mm Size
  • The top surface of this plate is precision ground to achieve a high degree of flatness and the flatness is 0.0029mm. It is a Grade A (Grade 00) plate and meets DIN876. Weighs 27 lbs.
  • Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
  • Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
  • They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive. Harder than steel and does not nick or burr.
  • Surface plates are offered by HHIP in various sizes and brands, with different levels of flatness and accuracy and are checked by an auto collimator for overall accuracy assurance.
No. 8
INSIZE 6900-A23 Granite Surface Plate, 24" x 36" x 4", Grade A
  • Made of granite, free from deterioration or dimensional change over time
  • Minimal changes in dimension due to temperature changes. Meet ggg-p-463c
  • Optional accessory: stand for granite surface plate (part no. 6902)
  • Jack for granite surface plate (part no. 6903)
No. 9
Dasqua 8500-0043 Grade A Granite Surface Plate for Precision Measurement, 400 x 250 x 70 mm Size
  • The top surface of this plate is precision ground to achieve a high degree of flatness and the flatness is 0.0029mm. It is a Grade A (Grade 00) plate and meets DIN876. Weighs 51 lbs.
  • Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
  • Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
  • They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive. Harder than steel and does not nick or burr.
  • Surface plates are offered by HHIP in various sizes and brands, with different levels of flatness and accuracy and are checked by an auto collimator for overall accuracy assurance.
No. 10
Shars 1" x 2" x 12" 2 Face Black Granite Parallel 1 Pair 2 Faces 0.00005" New 303-9159 R
  • Parallel Thickness: 1
  • Overall Length: 12
  • Product Height: 2
  • Parallelism: 0.00005" Per 6
  • Number of Pairs: 1

Last update on 2026-07-18 / Affiliate links / Images from Amazon Product Advertising API

How to Choose the Best Calibration Surface Plates

Understanding Surface Plate Materials

The material of a surface plate significantly impacts its durability, accuracy, and cost. Common options include:

  • Granite: Known for its hardness, stability, and resistance to wear and corrosion. It's a popular choice for precision applications due to its low thermal expansion.
  • Cast Iron: Offers good rigidity and stability but can be susceptible to rust and requires more maintenance. It's often a more economical option for general-purpose use.
  • Ceramic: Lightweight, non-magnetic, and highly resistant to heat and corrosion. Ceramic plates are ideal for specialized environments but can be more brittle.

Key Features to Consider

Beyond material, several features enhance a surface plate's utility:

  • Accuracy Grade: Surface plates are graded according to national standards (e.g., ASME B89.3.7). Higher grades (like Grade AA) offer greater flatness and are suitable for calibration and inspection, while lower grades (like Grade B) are for general shop use.
  • Size and Thickness: The plate's dimensions should accommodate the size of the items you intend to measure or calibrate. Ensure it's thick enough to prevent deflection under load.
  • Leveling Legs/Supports: Adjustable legs or a stable support system are essential for ensuring the plate is perfectly level, which is critical for accurate measurements.
  • Accessories: Consider if you need additional accessories like leveling instruments, surface plate cleaners, or storage covers.

Calibration and Maintenance

Regular calibration is vital to maintain the accuracy of your surface plate. The frequency depends on usage and the required precision. Proper maintenance, including cleaning and protection from impacts or contamination, will prolong its lifespan and ensure consistent performance.

Choosing the Right Size and Grade

When selecting a surface plate, consider the largest workpiece you will be measuring. A general rule is to have at least 30% of the workpiece surface in contact with the plate. For critical inspection and calibration tasks, opt for a higher accuracy grade. For general layout and assembly, a lower grade may suffice. Always ensure the plate is adequately supported and leveled.

Frequently Asked Questions

What is the primary purpose of a calibration surface plate?
A calibration surface plate provides a highly accurate and flat reference surface. It's used for precision measurements, layout work, inspection, and calibration of other measuring instruments.
How often should a surface plate be calibrated?
The calibration frequency depends on its usage and the required precision. For critical applications, annual calibration is common. For less demanding use, it might be every two years, or after a significant event like a drop or impact.
What does 'accuracy grade' mean for a surface plate?
Accuracy grade refers to the allowable deviation from perfect flatness. Higher grades, like AA, have tighter tolerances and are suitable for precision calibration, while lower grades are for general shop use.
Can I use a cast iron surface plate outdoors?
It is generally not recommended to use cast iron surface plates outdoors. Cast iron is susceptible to rust and corrosion, and environmental factors can affect its stability and accuracy.
What is the best way to clean a granite surface plate?
Clean granite surface plates with a mild, non-abrasive cleaner and a soft cloth. Avoid harsh chemicals or abrasive pads that could scratch the surface. Ensure it's dry before use or storage.
How do I ensure my surface plate is perfectly level?
Use a precision level placed at multiple points across the surface. Adjust the leveling legs or supports until the plate is level in both directions (e.g., front-to-back and side-to-side).