Quick check
Table search
Filter the table by size, symbol, process, value, or application without scanning the whole chart.
Mechanical design reference
Search common engineering drawing symbols and notes for fabrication, inspection, weld documentation, and manufacturing communication.
Design reference
Use the searchable table to filter the reference data by the values, symbols, sizes, and applications that matter for your design check.
Quick check
Filter the table by size, symbol, process, value, or application without scanning the whole chart.
Quick check
Use the table for early sizing and drawing checks, then confirm final values against the governing standard.
Reference table
| Symbol | Description | Feature Control / Tolerance Type | Notes |
|---|---|---|---|
| ⌖ | Position | Feature location | Specifies true position of a feature |
| ⏀ | Flatness | Form | Ensures surface lies in a single plane |
| ⏃ | Straightness | Form | Surface or axis must be straight |
| ⏄ | Circularity / Roundness | Form | Feature cross-section must be circular |
| ⏅ | Cylindricity | Form | Entire cylindrical surface must meet tolerance |
| ⏆ | Profile of a Line | Profile | Controls shape along a line of surface |
| ⏇ | Profile of a Surface | Profile | Controls entire surface shape |
| ⏈ | Angularity | Orientation | Feature must be at specified angle to datum |
| ⏉ | Perpendicularity | Orientation | Feature must be 90° to datum plane/axis |
| ⏊ | Parallelism | Orientation | Feature must be parallel to datum |
| ⏋ | Concentricity / Coaxiality | Location | Centers of features must coincide |
| ⏌ | Symmetry | Location | Feature must be symmetrical about datum axis/plane |
| ⏍ | Runout | Runout / Circular Runout | Controls surface rotation relative to datum |
How to use
mm = in × 25.4
Use this for inch-to-metric conversions where the page includes dimensional data.
clearance = hole size - feature size
Positive clearance helps confirm whether a part can assemble freely.
range = upper limit - lower limit
The usable manufacturing window is the difference between upper and lower limits.
value + unit + standard
Reference data is most useful when paired with units and the governing drawing or design standard.
Definitions
A tabulated value used for selection, comparison, or early design checks.
The named or target size before manufacturing tolerance is applied.
The allowed variation from the nominal or specified value.
The source convention or governing document that defines how a value should be interpreted.
FAQ
Use it for quick comparison, preliminary design, drawing review, and shop reference.
No. Use this page as a fast reference; final design and inspection should follow the current standard, drawing notes, and project requirements.
Search helps you jump directly to a size, symbol, process, value, or application without scanning every row.
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