Inch Thread Gage Pitch Diameters

(Sizes 9/16" Through 1")

Typical thread class usage:

A class 1A external thread and a class 1B internal thread gives a loose fit.

A class 2A external thread and a class 2B internal thread gives a normal fit.

A class 3A external thread and a class 3B internal thread gives a close fit.

Classes 1A, 2A, and 3A gages are thread ring gages to check external threads.

Classes 1B, 2B, and 3B gages are thread plug gages to check internal threads.

Previous Page
Next Page
Fractional Thread Size
Decimal Thread Size
Go Pitch Diameter

(P.D.)

No Go Pitch Diameter

(P.D.)

9/16-12 UNC-1A
.5625-12 UNC-1A
.5068"
.4990"
9/16-12 UNC-1B
.5625-12 UNC-1B
.5084"
.5186"
9/16-12 UNC-2A
.5625-12 UNC-2A
.5068"
.5016"
9/16-12 UNC-2B
.5625-12 UNC-2B
.5084"
.5152"
9/16-12 UNC-3A
.5625-12 UNC-3A
.5084"
.5045"
9/16-12 UNC-3B
.5625-12 UNC-3B
.5084"
.5135"
9/16-14 UNS-2A
.5625-14 UNS-2A
.5146"
.5096"
9/16-14 UNS-2B
.5625-14 UNS-2B
.5161"
.5226"
9/16-16 UN-2A
.5625-16 UN-2A
.5205"
.5158"
9/16-16 UN-2B
.5625-16 UN-2B
.5219"
.5280"
9/16-16 UN-3A
.5625-16 UN-3A
.5219"
.5184"
9/16-16 UN-3B
.5625-16 UN-3B
.5219"
.5265"
9/16-18 UNF-1A
.5625-18 UNF-1A
.5250"
.5182"
9/16-18 UNF-1B
.5625-18 UNF-1B
.5264"
.5353"
9/16-18 UNF-2A
.5625-18 UNF-2A
.5250"
.5205"
9/16-18 UNF-2B
.5625-18 UNF-2B
.5264"
.5323"
9/16-18 UNF-3A
.5625-18 UNF-3A
.5264"
.5230"
9/16-18 UNF-3B
.5625-18 UNF-3B
.5264"
.5308"
9/16-20 UN-2A
.5625-20 UN-2A
.5287"
.5245"
9/16-20 UN-2B
.5625-20 UN-2B
.5300"
.5355"
9/16-20 UN-3A
.5625-20 UN-3A
.5300"
.5268"
9/16-20 UN-3B
.5625-20 UN-3B
.5300"
.5341"
9/16-24 UNEF-2A
.5625-24 UNEF-2A
.5342"
.5303"
9/16-24 UNEF-2B
.5625-24 UNEF-2B
.5354"
.5405"
9/16-24 UNEF-3A
.5625-24 UNEF-3A
.5354"
.5325"
9/16-24 UNEF-3B
.5625-24 UNEF-3B
.5354"
.5392"
9/16-27 UNS-2A
.5625-27 UNS-2A
.5373"
.5336"
9/16-27 UNS-2B
.5625-27 UNS-2B
.5384"
.5432"
9/16-28 UN-2A
.5625-28 UN-2A
.5382"
.5345"
9/16-28 UN-2B
.5625-28 UN-2B
.5393"
.5365"
9/16-28 UN-3A
.5625-28 UN-3A
.5393"
.0939"
9/16-28 UN-3B
.5625-28 UN-3B
.5393"
.5429"
9/16-32 UN-2A
.5625-32 UN-2A
.5412"
.5377"
9/16-32 UN-2B
.5625-32 UN-2B
.5422"
.5467"
9/16-32 UN-3A
.5625-32 UN-3A
.5422"
.5396"
9/16-32 UN-3B
.5625-32 UN-3B
.5422"
.5456"
5/8-11 UNC-1A
.6250-11 UNC-1A
.5644"
.5561"
5/8-11 UNC-1B
.6250-11 UNC-1B
.5660"
.5767"
5/8-11 UNC-2A
.6250-11 UNC-2A
.5644"
.5589"
5/8-11 UNC-2B
.6250-11 UNC-2B
.5660"
.5732"
5/8-11 UNC-3A
.6250-11 UNC-3A
.5660"
.5619"
5/8-11 UNC-3B
.6250-11 UNC-3B
.5660"
.5714"
5/8-12 UN-2A
.6250-12 UN-2A
.5693"
.5639"
5/8-12 UN-2B
.6250-12 UN-2B
.5709"
.5780"
5/8-12 UN-3A
.6250-12 UN-3A
.5709"
.5668"
5/8-12 UN-3B
.6250-12 UN-3B
.5709"
.5762"
5/8-14 UNS-2A
.6250-14 UNS-2A
.5771"
.5720"
5/8-14 UNS-2B
.6250-14 UNS-2B
.5786"
.5852"
5/8-16 UN-2A
.6250-16 UN-2A
.5830"
.5782"
5/8-16 UN-2B
.6250-16 UN-2B
.5844"
.5906"
5/8-16 UN-3A
.6250-16 UN-3A
.5844"
.5808"
5/8-16 UN-3B
.6250-16 UN-3B
.5844"
.5890"
5/8-18 UNF-1A
.6250-18 UNF-1A
.5875"
.5805"
5/8-18 UNF-1B
.6250-18 UNF-1B
.5889"
.5980"
5/8-18 UNF-2A
.6250-18 UNF-2A
.5875"
.5828"
5/8-18 UNF-2B
.6250-18 UNF-2B
.5889"
.5949"
5/8-18 UNF-3A
.6250-18 UNF-3A
.5889"
.5854"
5/8-18 UNF-3B
.6250-18 UNF-3B
.5889"
.5934"
5/8-20 UN-2A
.6250-20 UN-2A
.5912"
.5869"
5/8-20 UN-2B
.6250-20 UN-2B
.5925"
.5981"
5/8-20 UN-3A
.6250-20 UN-3A
.5925"
.5893"
5/8-20 UN-3B
.6250-20 UN-3B
.5925"
.5967"
5/8-24 UNEF-2A
.6250-24 UNEF-2A
.5967"
.5927"
5/8-24 UNEF-2B
.6250-24 UNEF-2B
.5979"
.6031"
5/8-24 UNEF-3A
.6250-24 UNEF-3A
.5979"
.5949"
5/8-24 UNEF-3B
.6250-24 UNEF-3B
.5979"
.6018"
5/8-27 UNS-2A
.6250-27 UNS-2A
.5998"
.5960"
5/8-27 UNS-2B
.6250-27 UNS-2B
.6009"
.6059"
5/8-28 UN-2A
.6250-28 UN-2A
.6007"
.5969"
5/8-28 UN-2B
.6250-28 UN-2B
.6018"
.6067"
5/8-28 UN-3A
.6250-28 UN-3A
.6018"
.5990"
5/8-28 UN-3B
.6250-28 UN-3B
.6018"
.6055"
5/8-32 UN-2A
.6250-32 UN-2A
.6036"
.6000"
5/8-32 UN-2B
.6250-32 UN-2B
.6047"
.6093"
5/8-32 UN-3A
.6250-32 UN-3A
.6047"
.6020"
5/8-32 UN-3B
.6250-32 UN-3B
.6047"
.6082"
11/16-12 UN-2A
.6875-12 UN-2A
.6318"
.6264"
11/16-12 UN-2B
.6875-12 UN-2B
.6334"
.6405"
11/16-12 UN-3A
.6875-12 UN-3A
.6334"
.6293"
11/16-12 UN-3B
.6875-12 UN-3B
.6334"
.6387"
11/16-16 UN-2A
.6875-16 UN-2A
.6455"
.6407"
11/16-16 UN-2B
.6875-16 UN-2B
.6469"
.6531"
11/16-16 UN-3A
.6875-16 UN-3A
.6469"
.6433"
11/16-16 UN-3B
.6875-16 UN-3B
.6469"
.6515"
11/16-20 UN-2A
.6875-20 UN-2A
.6537"
.6494"
11/16-20 UN-2B
.6875-20 UN-2B
.6550"
.6606"
11/16-20 UN-3A
.6875-20 UN-3A
.6550"
.6518"
11/16-20 UN-3B
.6875-20 UN-3B
.6550"
.6592"
11/16-24 UNEF-2A
.6875-24 UNEF-2A
.6592"
.6552"
11/16-24 UNEF-2B
.6875-24 UNEF-2B
.6604"
.6656"
11/16-24 UNEF-3A
.6875-24 UNEF-3A
.6604"
.6574"
11/16-24 UNEF-3B
.6875-24 UNEF-3B
.6604"
.6643"
11/16-28 UN-2A
.6875-28 UN-2A
.6632"
.6594"
11/16-28 UN-2B
.6875-28 UN-2B
.6643"
.6692"
11/16-28 UN-3A
.6875-28 UN-3A
.6643"
.6615"
11/16-28 UN-3B
.6875-28 UN-3B
.6643"
.6680"
11/16-32 UN-2A
.6875-32 UN-2A
.6661"
.6625"
11/16-32 UN-2B
.6875-32 UN-2B
.6672"
.6718"
11/16-32 UN-3A
.6875-32 UN-3A
.6672"
.6645"
11/16-32 UN-3B
.6875-32 UN-3B
.6672"
.6707"
3/4-10 UNC-1A
.7500-10 UNC-1A
.6832"
.6744"
3/4-10 UNC-1B
.7500-10 UNC-1B
.6850"
.6965"
3/4-10 UNC-2A
.7500-10 UNC-2A
.6832"
.6773"
3/4-10 UNC-2B
.7500-10 UNC-2B
.6850"
.6927"
3/4-10 UNC-3A
.7500-10 UNC-3A
.6850"
.6806"
3/4-10 UNC-3B
.7500-10 UNC-3B
.6850"
.6907"
3/4-12 UN-2A
.7500-12 UN-2A
.6942"
.6887"
3/4-12 UN-2B
.7500-12 UN-2B
.6959"
.7031"
3/4-12 UN-3A
.7500-12 UN-3A
.6959"
.6918"
3/4-12 UN-3B
.7500-12 UN-3B
.6959"
.7103"
3/4-14 UNS-2A
.7500-14 UNS-2A
.7021"
.6970"
3/4-14 UNS-2B
.7500-14 UNS-2B
.7036"
.7103"
3/4-16 UNF-1A
.7500-16 UNF-1A
.7079"
.7004"
3/4-16 UNF-1B
.7500-16 UNF-1B
.7094"
.7192"
3/4-16 UNF-2A
.7500-16 UNF-2A
.7079"
.7029"
3/4-16 UNF-2B
.7500-16 UNF-2B
.7094"
.7159"
3/4-16 UNF-3A
.7500-16 UNF-3A
.7094"
.7056"
3/4-16 UNF-3B
.7500-16 UNF-3B
.7094"
.7143"
3/4-18 UNS-2A
.7500-18 UNS-2A
.7125"
.7079"
3/4-18 UNS-2B
.7500-18 UNS-2B
.7139"
.7199"
3/4-20 UNEF-2A
.7500-20 UNEF-2A
.7162"
.7118"
3/4-20 UNEF-2B
.7500-20 UNEF-2B
.7175"
.7232"
3/4-20 UNEF-3A
.7500-20 UNEF-3A
.7175"
.7142"
3/4-20 UNEF-3B
.7500-20 UNEF-3B
.7175"
.7218"
3/4-24 UNS-2A
.7500-24 UNS-2A
.7217"
.7176"
3/4-24 UNS-2B
.7500-24 UNS-2B
.7229"
.7282"
3/4-27 UNS-2A
.7500-27 UNS-2A
.7247"
.7208"
3/4-27 UNS-2B
.7500-27 UNS-2B
.7259"
.7310"
3/4-28 UN-2A
.7500-28 UN-2A
.7256"
.7218"
3/4-28 UN-2B
.7500-28 UN-2B
.7268"
.7318"
3/4-28 UN-3A
.7500-28 UN-3A
.7268"
.7239"
3/4-28 UN-3B
.7500-28 UN-3B
.7268"
.7305"
3/4-32 UN-2A
.7500-32 UN-2A
.7286"
.7250"
3/4-32 UN-2B
.7500-32 UN-2B
.7297"
.7344"
3/4-32 UN-3A
.7500-32 UN-3A
.7297"
.7270"
3/4-32 UN-3B
.7500-32 UN-3B
.7297"
.7333"
13/16-12 UN-2A
.8125-12 UN-2A
.7567"
.7512"
13/16-12 UN-2B
.8125-12 UN-2B
.7584"
.7656"
13/16-12 UN-3A
.8125-12 UN-3A
.7584"
.7543"
13/16-12 UN-3B
.8125-12 UN-3B
.7584"
.7638"
13/16-16 UN-2A
.8125-16 UN-2A
.7704"
.7655"
13/16-16 UN-2B
.8125-16 UN-2B
.7719"
.7782"
13/16-16 UN-3A
.8125-16 UN-3A
.7719"
.7683"
13/16-16 UN-3B
.8125-16 UN-3B
.7719"
.7766"
13/16-20 UNEF-2A
.8125-20 UNEF-2A
.7787"
.7743"
13/16-20 UNEF-2B
.8125-20 UNEF-2B
.7800"
.7857"
13/16-20 UNEF-3A
.8125-20 UNEF-3A
.7800"
.7767"
13/16-20 UNEF-3B
.8125-20 UNEF-3B
.7800"
.7843"
13/16-28 UN-2A
.8125-28 UN-2A
.7881"
.7843"
13/16-28 UN-2B
.8125-28 UN-2B
.7893"
.7943"
13/16-28 UN-3A
.8125-28 UN-3A
.7893"
.7864"
13/16-28 UN-3B
.8125-28 UN-3B
.7893"
.7930"
13/16-32 UN-2A
.8125-32 UN-2A
.7911"
.7875"
13/16-32 UN-2B
.8125-32 UN-2B
.7922"
.7969"
13/16-32 UN-3A
.8125-32 UN-3A
.7922"
.7895"
13/16-32 UN-3B
.8125-32 UN-3B
.7922"
.7958"
7/8-9 UNC-1A
.8750-9 UNC-1A
.8009"
.7914"
7/8-9 UNC-1B
.8750-9 UNC-1B
.8028"
.8151"
7/8-9 UNC-2A
.8750-9 UNC-2A
.8009"
.7946"
7/8-9 UNC-2B
.8750-9 UNC-2B
.8028"
.8110"
7/8-9 UNC-3A
.8750-9 UNC-3A
.8028"
.7981"
7/8-9 UNC-3B
.8750-9 UNC-3B
.8028"
.8089"
7/8-10 UNS-2A
.8750-10 UNS-2A
.8082"
.8022"
7/8-10 UNS-2B
.8750-10 UNS-2B
.8100"
.8178"
7/8-12 UN-2A
.8750-12 UN-2A
.8192"
.8137"
7/8-12 UN-2B
.8750-12 UN-2B
.8209"
.8281"
7/8-12 UN-3A
.8750-12 UN-3A
.8209"
.8168"
7/8-12 UN-3B
.8750-12 UN-3B
.8209"
.8263"
7/8-14 UNF-1A
.8750-14 UNF-1A
.8270"
.8189"
7/8-14 UNF-1B
.8750-14 UNF-1B
.8286"
.8392"
7/8-14 UNF-2A
.8750-14 UNF-2A
.8270"
.8216"
7/8-14 UNF-2B
.8750-14 UNF-2B
.8286"
.8356"
7/8-14 UNF-3A
.8750-14 UNF-3A
.8286"
.8245"
7/8-14 UNF-3B
.8750-14 UNF-3B
.8286"
.8339"
7/8-16 UN-2A
.8750-16 UN-2A
.8329"
.8280"
7/8-16 UN-2B
.8750-16 UN-2B
.8344"
.8407"
7/8-16 UN-3A
.8750-16 UN-3A
.8344"
.8308"
7/8-16 UN-3B
.8750-16 UN-3B
.8344"
.8391"
7/8-18 UNS-2A
.8750-18 UNS-2A
.8375"
.8329"
7/8-18 UNS-2B
.8750-18 UNS-2B
.8389"
.8449"
7/8-20 UNEF-2A
.8750-20 UNEF-2A
.8412"
.8368"
7/8-20 UNEF-2B
.8750-20 UNEF-2B
.8425"
.8482"
7/8-20 UNEF-3A
.8750-20 UNEF-3A
.8425"
.8392"
7/8-20 UNEF-3B
.8750-20 UNEF-3B
.8425"
.8468"
7/8-24 UNS-2A
.8750-24 UNS-2A
.8467"
.8426"
7/8-24 UNS-2B
.8750-24 UNS-2B
.8479"
.8532"
7/8-27 UNS-2A
.8750-27 UNS-2A
.8497"
.8458"
7/8-27 UNS-2B
.8750-27 UNS-2B
.8509"
.8560"
7/8-28 UN-2A
.8750-28 UN-2A
.8506"
.8468"
7/8-28 UN-2B
.8750-28 UN-2B
.8518"
.8568"
7/8-28 UN-3A
.8750-28 UN-3A
.8518"
.8489"
7/8-28 UN-3B
.8750-28 UN-3B
.8518"
.8555"
7/8-32 UN-2A
.8750-32 UN-2A
.8536"
.8500"
7/8-32 UN-2B
.8750-32 UN-2B
.8547"
.8594"
7/8-32 UN-3A
.8750-32 UN-3A
.8547"
.8520"
7/8-32 UN-3B
.8750-32 UN-3B
.8547"
.8583"
15/16-12 UN-2A
.9375-12 UN-2A
.8817"
.8760"
15/16-12 UN-2B
.9375-12 UN-2B
.8834"
.8908"
15/16-12 UN-3A
.9375-12 UN-3A
.8834"
.8793"
15/16-12 UN-3B
.9375-12 UN-3B
.8834"
.8889"
15/16-16 UN-2A
.9375-16 UN-2A
.8954"
.8904"
15/16-16 UN-2B
.9375-16 UN-2B
.8969"
.9034"
15/16-16 UN-3A
.9375-16 UN-3A
.8969"
.8932"
15/16-16 UN-3B
.9375-16 UN-3B
.8969"
.9018"
15/16-20 UNEF-2A
.9375-20 UNEF-2A
.9036"
.8991"
15/16-20 UNEF-2B
.9375-20 UNEF-2B
.9050"
.9109"
15/16-20 UNEF-3A
.9375-20 UNEF-3A
.9050"
.9016"
15/16-20 UNEF-3B
.9375-20 UNEF-3B
.9050"
.9094"
15/16-28 UN-2A
.9375-28 UN-2A
.9131"
.9091"
15/16-28 UN-2B
.9375-28 UN-2B
.9143"
.9195"
15/16-28 UN-3A
.9375-28 UN-3A
.9143"
.9113"
15/16-28 UN-3B
.9375-28 UN-3B
.9143"
.9182"
15/16-32 UN-2A
.9375-32 UN-2A
.9161"
.9123"
15/16-32 UN-2B
.9375-32 UN-2B
.9172"
.9221"
15/16-32 UN-3A
.9375-32 UN-3A
.9172"
.9144"
15/16-32 UN-3B
.9375-32 UN-3B
.9172"
.9209"
1-8 UNC-1A
1.0000-8 UNC-1A
.9168"
.9067"
1-8 UNC-1B
1.0000-8 UNC-1B
.9188"
.9320"
1-8 UNC-2A
1.0000-8 UNC-2A
.9168"
.9100"
1-8 UNC-2B
1.0000-8 UNC-2B
.9188"
.9276"
1-8 UNC-3A
1.0000-8 UNC-3A
.9188"
.9137"
1-8 UNC-3B
1.0000-8 UNC-3B
.9188"
.9254"
1-10 UNS-2A
1.0000-10 UNS-2A
.9332"
.9270"
1-10 UNS-2B
1.0000-10 UNS-2B
.9350"
.9430"
1-12 UNF-1A
1.0000-12 UNF-1A
.9441"
.9353"
1-12 UNF-1B
1.0000-12 UNF-1B
.9459"
.9573"
1-12 UNF-2A
1.0000-12 UNF-2A
.9441"
.9382"
1-12 UNF-2B
1.0000-12 UNF-2B
.9459"
.9535"
1-12 UNF-3A
1.0000-12 UNF-3A
.9459"
.9415"
1-12 UNF-3B
1.0000-12 UNF-3B
.9459"
.9516"
1-14 UNS-1A
1.0000-14 UNS-1A
.9519"
.9435"
1-14 UNS-1B
1.0000-14 UNS-1B
.9536"
.9645"
1-14 UNS-2A
1.0000-14 UNS-2A
.9520"
.9467"
1-14 UNS-2B
1.0000-14 UNS-2B
.9536"
.9605"
1-14 UNS-3A
1.0000-14 UNS-3A
.9536"
.9496"
1-14 UNS-3B
1.0000-14 UNS-3B
.9536"
.9588"
1-16 UN-2A
1.0000-16 UN-2A
.9579"
.9529"
1-16 UN-2B
1.0000-16 UN-2B
.9594"
.9659"
1-16 UN-3A
1.0000-16 UN-3A
.9594"
.9557"
1-16 UN-3B
1.0000-16 UN-3B
.9594"
.9643"
1-18 UNS-2A
1.0000-18 UNS-2A
.9625"
.9578"
1-18 UNS-2B
1.0000-18 UNS-2B
.9639"
.9701"
1-20 UNEF-2A
1.0000-20 UNEF-2A
.9661"
.9616"
1-20 UNEF-2B
1.0000-20 UNEF-2B
.9675"
.9734"
1-20 UNEF-3A
1.0000-20 UNEF-3A
.9675"
.9641"
1-20 UNEF-3B
1.0000-20 UNEF-3B
.9675"
.9719"
1-24 UNS-2A
1.0000-24 UNS-2A
.9716"
.9674"
1-24 UNS-2B
1.0000-24 UNS-2B
.9729"
.9784"
1-27 UNS-2A
1.0000-27 UNS-2A
.9747"
.9707"
1-27 UNS-2B
1.0000-27 UNS-2B
.9759"
.9811"
1-28 UN-2A
1.0000-28 UN-2A
.9756"
.9716"
1-28 UN-2B
1.0000-28 UN-2B
.9768"
.9820"
1-28 UN-3A
1.0000-28 UN-3A
.9768"
.9738"
1-28 UN-3B
1.0000-28 UN-3B
.9768"
.9807"
1-32 UN-2A
1.0000-32 UN-2A
.9786"
.9748"
1-32 UN-2B
1.0000-32 UN-2B
.9797"
.9846"
1-32 UN-3A
1.0000-32 UN-3A
.9797"
.9769"
1-32 UN-3B
1.0000-32 UN-3B
.9797"
.9834"
Previous Page
Next Page
© 2007-2011 Great Lakes Gage Sales, Inc. Site Map