GD&T Symbols and Guidelines Cheat Sheet
Provided by GD&T Basics - www.gdandtbasics.com
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Y
V
Y
The 4 Fundamental
Elements of GD&T:
X
X
Size
Z
Location
Z
W
U
Orientation
X
X
Form
All drawings made in
first angle projection
SYMBOL
NAME
ON DRAWING
Straightness
TOLERANCE ZONE
GAUGING
SURFACES
FEATURES OF SIZE
Two parallel lines
0.03 apart
0.03
(Surface)
M
10±0.050
0.03 M
Straightness
(Derived Median Line w/
M
Gauge ID = 10.08
0.03
FORM
Flatness
(Derived Median
Plane w/ M )
Circularity
Cylindricity
Perpendicularity
0.03
Two concentric cylinders
0.03 apart
Two parallel planes
0.03 apart
parallel to datum
Gauge kept parallel to datum
Two parallel planes
0.03 apart
Flat datum block
(Datum A)
A
Datum A
90°
10±0.05
0.03 M A
Perpendicularity
Gauge kept perpendicular to datum
Axis
Tolerance Zone
at M
0.03 A
Multiple datums
may be used
to specify
Perpendicularity
Datum A
Z
W
U
X
W
Z
U
X
60°
60
°
Uniform Linear Boundary About True Profile
0.03 apart
0.03 A B
Datum B
SLOF
Gauge must
follow true profile.
A
Profile is usually
measured with a CMM.
Basic dimensions (not shown) are required to
define the True Profile when datums are used.
Datum A
Y
Y
V
Profile
of a surface
B
Gauge must
follow true profile.
A
X
Profile is usually
measured with a CMM.
Basic dimensions (not shown) are required to
define the True Profile when datums are used.
20.0
True
30.0
True Position
(Maximum Material
Condition)
A
25.0
True X Actual X
Actual
Pin Position
A
For an
External
Feature
Gauge Hole ∅ = Virtual Condition
(Largest Pin Size [MMC] + Position Tol.)
Tolerance Zone
of Pin Gauge
Gauge
For an
Internal
Feature
Y
V
Actual
Hole Position
Gauge
A
Datum A
Tolerance Zone
The following is usually
done with a CMM:
1. Determine
Datum axis
2. Measure referenced
surface
3. Determine if central
axis falls in TZ
Diameter Symbol is required
A
A
The following is
usually done
with a CMM:
1. Determine
Datum plane
2. Measure both
surfaces of features
3. Determine if
midpoints fall in TZ
A
Datum A
Plane
Symmetry
1
Two parallel planes
0.03 apart
0.03 A
A
Datum A
Fixed axially
+ Rotated
A
U
Y
Z
X
Y
V
Z
W
U
LOF
Can also be used
on flat surfaces
perpendicular
to the datum axis
A
Y
Y
V
0.03 A
A
Total Runout
A
Datum A
Fixed axially
+ Rotated
A
Datum A
Fixed + Rotated
Can also be used
on flat surfaces
perpendicular
to the datum axis
A
Copyright © Pareto Learning LLC - All Rights Reserved - Chart designed by Andrea Barbieri <www.andreabarbieri.net>
Z
X
LOF
Distribution/
Evenness of
Form Only
Datum A
Fixed + Rotated
A
W
Z
Gauge Pin ∅ = Virtual Condition
(Smallest Hole Size [MMC] - Position Tol.)
Datum axis
A
X
True
position
0.03
Runout
Z
1
Measured axis
0.03 A
LO
Y
Part
0.03 A
Concentricity
X
None
FUNCTIONAL
GAUGING
Part
Tolerance Zone
of Hole Gauge
C
U
X
True
position
25.0
W
Z
This formula must be less than
the ∅ True Position tolerance
Actual Y
True Y
0.03
True
center
B
X
2X √ (Actual X - True X)2 + (Actual Y - True Y)2
Actual
10±0.05
0.03 M A B C
Z
Measure X and Y location and compare to the true position.
Part (actual) position
Y
C
X
Datum A
B
True Position
M
Datum B
Uniform Surface Boundary About True Profile
0.03 apart
0.03 A B
10±0.05
0.03 A B C
RUNOUT
V
Gauge
Block
A
B
Y
Two parallel planes
0.03 apart
60°
Profile
of a line
Y
Pin Gauge ∅ = 9.92
(9.95 - 0.03)
Datum A
60°
O
V
90°
A
OF
Pin Gauge OD = M −
Gauge pin
inserted
perpendicular
to datum
(Feature of Size w/ M )
Angularity
= 10.08
Flat datum block
(Datum A)
Datum A
0.03 A
(Feature)
PROFILE
M +
0.03
A
(Derived Median
Line and Plane)
Gauge spacing
at Virtual Condition
Two concentric circles
0.03 apart
0.03 A
Parallelism
M
Planar Tolerance Zone
Two parallel planes
0.03 apart
10±0.05
0.03 M
F
F
Two parallel planes
0.03 apart
(Surface)
M
LOCATION
Cylinder Gauge ID = M +
)
Flatness
ORIENTATION
Cylindrical Tolerance Zone
0.03 when Part ∅ = 10.05
0.13 when Part ∅ = 9.95
X
Z
W
U
X
X
(Derived
Median
Points)