Best Calibration Surface Plates for Calibrating Instruments (2026)
We ranked plates by flatness grade, available sizes and thicknesses, material (granite), and value relative to typical price bands for calibration tools
This roundup covers granite calibration surface plates used for flatness checks and instrument setup, ranked for fit and value using measurable features. Selections prioritize plate grade, size options, and durability to help technicians choose the right reference surface for calibration tasks
Top Picks
-
1
HHIP Granite Surface Plate, Grade B, 12 x 9 x 3
Granite surface plate precision ground for flatness. Grade B with certificate of inspection (not NIST traceable). Useful for measuring, laying out parts, and calibrating instruments. Customers note good size and weight, with mixed views on flatness and surface finish
- precision-ground surface
- certificate of inspection
- sturdy granite plate
-
2
HHIP granite surface plate 6x8x2, grade B, with certificate
Granite surface plate precision ground for flatness; Grade B with certificate of inspection. Useful for measuring, laying out parts, and calibrating tools. Customers note solid size for small shops and weight as a plus
- precision ground surface
- certificate of inspection included
- suitable for small shops
-
3
HHIP Granite Surface Plate 12" x 8" x 2" Grade B
Granite surface plate precision ground for flatness with a Grade B rating. Includes a certificate of inspection and meets specification standards. Customers note good size and weight for small shops, with mixed views on flatness and surface smoothness
- precision-ground top surface
- certificate of inspection
- grade B plate
-
4
HHIP 6x6x2 Granite Surface Plate, Grade B, 0 Ledge
Granite surface plate with precision-ground top for flatness. Includes certificate of inspection; not NIST traceable. Useful for measuring flatness, squareness, and setup of tools. Customers note good size and weight for small shops, with mixed views on flatness and surface finish
- precision-ground top
- certificate of inspection
- compact granite plate
-
5
HHIP granite surface plate 11.81 x 7.87 x 2.36 Grade A
Granite surface plate precision ground for flatness with Grade A accuracy. Includes certificate of inspection and non-NIST traceable. Useful for measuring flatness, squareness, layout, and tool setup. Customers note good size and weight for small shops
- precision ground surface
- Grade A accuracy
- certificate of inspection
-
6
HHIP Granite Surface Plate 15.7 x 9.8 x 2.36 in Grade A
Granite surface plate, precision ground top for flatness. Grade A (Grade 0) with inspection certificate. Useful for measuring flatness, squareness, layout, and tool setup; customers note good size and weight
- Grade A surface plate
- certificate of inspection included
- precision-ground granite surface
-
7
HHIP granite surface plate 15.7 x 15.7 x 2.36 in, grade A
Granite surface plate with precision ground top for flatness. Includes a certificate of inspection (not NIST traceable). Useful for measuring, laying out parts, and calibrating tools; valued for size and weight from user feedback
- precision-ground top
- certificate of inspection
- compact, stable size
-
8
HHIP 4401-2418 Granite Surface Plate, Grade A, 24 x 18 x 3 in
Granite surface plate with precision ground top for flatness accuracy. Includes certificate of inspection; not NIST traceable. Good for measuring flatness, squareness, and layout tasks; customers cite solid size and weight with mixed views on flatness and surface finish
- precision ground top
- certificate of inspection
- Grade A plate with specified accuracy