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Needle gauge comparison chart

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]


Overview

Overview

Hypodermic needles are available in a wide variety of outer diameters described by gauge numbers. Smaller gauge numbers indicate larger outer diameters. Inner diameter depends on both gauge and wall thickness. The following chart shows nominal inner diameter and wall thickness for regular-wall needles. Thin-wall needles (not shown) have identical outer diameters but larger inner diameters for a given gauge.

Needle Nominal Outer Diameter Nominal Inner Diameter Nominal Wall Thickness
Gauge inches mm tol. inches (mm) inches mm tol. inches (mm) inches mm tol. inches (mm)
7 0.180 4.572 ±0.001 (±0.025) 0.150 3.810 ±0.003 (±0.076) 0.015 0.381 ±0.001 (±0.025)
8 0.165 4.191 0.135 3.429
9 0.148 3.759 0.118 2.997
10 0.134 3.404 0.106 2.692 0.014 0.356
11 0.120 3.048 0.094 2.388 0.013 0.330
12 0.109 2.769 0.085 2.159 0.012 0.305
13 0.095 2.413 0.071 1.803
14 0.083 2.108 0.063 1.600 0.01 0.254
15 0.072 1.829 ±0.0005 (±0.013) 0.054 1.372 ±0.0015 (±0.038) 0.009 0.229 ±0.0005 (±0.013)
16 0.065 1.651 0.047 1.194
17 0.058 1.473 0.042 1.067 0.008 0.203
18 0.050 1.270 0.033 0.838 0.0085 0.216
19 0.042 1.067 0.027 0.686 0.0075 0.191
20 0.03575 0.9081 ±0.00025 (±0.0064) 0.02375 0.603 ±0.00075 (±0.019) 0.006 0.1524 ±0.00025 (±0.0064)
21 0.03225 0.8192 0.02025 0.514
22 0.02825 0.7176 0.01625 0.413
22s 0.006 0.152 0.0111 0.2826
23 0.02525 0.6414 0.01325 0.337 0.006 0.1524
24 0.02225 0.5652 0.01225 0.311 0.005 0.1270
25 0.02025 0.5144 0.01025 0.260
26 0.01825 0.4636 0.004 0.1016
26s 0.01865 0.4737 0.005 0.127 0.0068 0.1734
27 0.01625 0.4128 0.00825 0.210 0.004 0.1016
28 0.01425 0.3620 0.00725 0.184 0.0035 0.0889
29 0.01325 0.3366 0.003 0.0762
30 0.01225 0.3112 0.00625 0.159
31 0.01025 0.2604 0.00525 0.133 0.0025 0.0635
32 0.00925 0.2350 0.00425 0.108
33 0.00825 0.2096 0.002 0.0508
34 0.00725 0.1842 0.00325 0.0826
See also

See also

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