GD&T · Runout · ASME Y14.5
Circular Runout GD&T Symbol — Meaning and Datum Rule
https://shopmath.org/gdt/circular-runout · data verified August 1, 2026
Circular Runout (↗) is a GD&T runout control, and its tolerance zone is full indicator movement in each single cross-section. It always references a datum.
- Symbol
- ↗
- Unicode
- U+2197
- Category
- Runout
- Datum
- always
Circular Runout · GD&T runout symbol
↗
- Unicode
- U+2197
- Datum
- always
- Zone
- Full indicator movement in each single cross-section
The value in the feature control frame is the width or diameter of that zone, in the drawing's units.
What Circular Runout Controls in GD&T
Measured by spinning the part about its datum axis and reading a fixed indicator at one cross-section: the total needle sweep must not exceed the tolerance. Each section is judged on its own, so circular runout catches roundness and centring errors but tolerates taper down the length.
The Circular Runout GD&T Symbol, Zone and Datum Rule
The symbol as it appears in the feature control frame, with the codepoint to type it and the rule it carries.
| Property | Value |
|---|---|
| Symbol | ↗ |
| Unicode codepoint | U+2197 |
| Category | Runout controls — Control composite error measured while the part rotates about a datum axis. |
| Tolerance zone | Full indicator movement in each single cross-section |
| Datum reference | Always references at least one datum. Without a datum reference frame the callout is incomplete and the drawing is ambiguous. |
| Standard | ASME Y14.5 (cited, not reproduced); ISO 1101 |
| Also called | runout, total runout vs circular runout |
The symbol character is the Unicode codepoint used in drawings and CAD annotations; drafting standards render it with defined proportions that the font approximates.
Sources and Method for the Circular Runout GD&T Reference
- Circular Runout symbol and rulescompiled
Symbols and codepoints: Unicode Character Database (Unicode License v3). Characteristic list cross-checked against NASA MSFC GD&T Basics (public domain). Descriptions written from scratch; no ASME Y14.5 text reproduced.
Verified against Unicode Character Database codepoint check; 98/98 structural checks passed
Compiled from independent public sources that agree cell-for-cell.
- Assumptions
- The standard is cited, never reproduced: no ASME Y14.5 definitional text, worked example or figure appears on this site. The description above is original prose.
- ASME Y14.5 and ISO 1101 differ in places — the ISO system uses the envelope requirement differently and does not carry every ASME modifier. Where a drawing names a standard, that standard governs.
- Dataset scope: EXCLUDED: all ASME Y14.5 definitional text, worked examples and figures. Every description on this site is original prose.
- Data last verified
- August 1, 2026
How to Cite This Circular Runout GD&T Reference
Citation
ShopMath. "Circular Runout GD&T Symbol — Meaning and Datum Rule." ShopMath, verified August 1, 2026, https://shopmath.org/gdt/circular-runout
BibTeX
@misc{shopmath-gdt-circular-runout,
title = {Circular Runout GD&T Symbol — Meaning and Datum Rule},
author = {{ShopMath}},
year = {2026},
howpublished = {\url{https://shopmath.org/gdt/circular-runout}},
note = {Data verified 2026-08-01}
}Permanent URL
https://shopmath.org/gdt/circular-runout
Common Questions About Circular Runout in GD&T
What does Circular Runout mean in GD&T?
- Measured by spinning the part about its datum axis and reading a fixed indicator at one cross-section: the total needle sweep must not exceed the tolerance. Each section is judged on its own, so circular runout catches roundness and centring errors but tolerates taper down the length.
What is the Circular Runout symbol in GD&T?
- ↗ — Unicode U+2197. It goes in the first compartment of the feature control frame, ahead of the tolerance value.
Does Circular Runout need a datum?
- Always references at least one datum. Without a datum reference frame the callout is incomplete and the drawing is ambiguous.
What shape is the Circular Runout tolerance zone?
- Full indicator movement in each single cross-section. Every point of the controlled feature has to lie inside that zone for the part to pass.
Which GD&T controls are in the same group as Circular Runout?
- Circular Runout is one of 2 runout controls: Circular Runout, Total Runout.