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OpenPose BODY_25 keypoints: the 25 body-part indices

25 body parts · from OpenPose poseParameters.cpp (branch master) · read 2026-10-17

OpenPose BODY_25 has 25 body parts, numbered from 0 Nose to 24 RHeel, as POSE_BODY_25_BODY_PARTS in OpenPose's src/openpose/pose/poseParameters.cpp defines them. The sources tie it to OpenPose BODY_25 model. 18 of the 25 names match a point in another scheme once lowercased with separators removed; the other 7 stay unmapped. Read from the sources on 2026-10-17.

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Models that output it

  • OpenPose BODY_25 model · OpenPose modelsEvidence: OpenPose output format doc (02_output.md) says “Pose Output Format (BODY_25)” (source).

Moving off OpenPose? See alternatives to OpenPose with BODY_25-style foot points.

All 25 body parts

Names are copied exactly from POSE_BODY_25_BODY_PARTS in OpenPose's src/openpose/pose/poseParameters.cpp. The index is the position the source assigns. The last column says whether another scheme on this site spells the same name, by the crosswalk rule.

IndexNameSame name in
0NoseBlazePose 33, ML Kit 33, COCO 17, Halpe26, COCO-WholeBody 133, OpenPose COCO 18, Apple Vision 2D
1NeckHalpe26, OpenPose COCO 18, Apple Vision 2D
2RShoulderOpenPose COCO 18
3RElbowOpenPose COCO 18
4RWristOpenPose COCO 18
5LShoulderOpenPose COCO 18
6LElbowOpenPose COCO 18
7LWristOpenPose COCO 18
8MidHipUnmapped
9RHipOpenPose COCO 18
10RKneeOpenPose COCO 18
11RAnkleOpenPose COCO 18
12LHipOpenPose COCO 18
13LKneeOpenPose COCO 18
14LAnkleOpenPose COCO 18
15REyeOpenPose COCO 18
16LEyeOpenPose COCO 18
17REarOpenPose COCO 18
18LEarOpenPose COCO 18
19LBigToeUnmapped
20LSmallToeUnmapped
21LHeelUnmapped
22RBigToeUnmapped
23RSmallToeUnmapped
24RHeelUnmapped

Not counted: the same map also lists 25 Background. The source excludes it from the body-part count: “POSE_NUMBER_BODY_PARTS equivalent to size of std::map POSE_BODY_XX_BODY_PARTS - 1 (removing background)”

What the sources say about the output

Copied from the sources, whitespace collapsed.

  • pose_keypoints_2d: Body part locations (x, y) and detection confidence (c) formatted as x0,y0,c0,x1,y1,c1,.... (OpenPose output format doc (02_output.md))
  • The coordinates x and y can be normalized to the range [0,1], [-1,1], [0, source size], [0, output size], etc. (see the flag --keypoint_scale for more information), while the confidence score (c) in the range [0,1]. (OpenPose output format doc (02_output.md))

How this list was checked

  • the map's keys run 0 to N-1
  • the map ends with {25, "Background"}, which the source excludes from the body-part count
  • POSE_NUMBER_BODY_PARTS gives POSE_BODY_25_BODY_PARTS 25 body parts
  • doc/02_output.md prints the same BODY_25 list
  • 18 of 25 names are shared with another scheme; the rest are listed as unmapped.

Other schemes

Questions

What are the 25 OpenPose BODY_25 body parts in index order?

POSE_BODY_25_BODY_PARTS in OpenPose's src/openpose/pose/poseParameters.cpp numbers them 0 Nose, 1 Neck, 2 RShoulder, 3 RElbow, 4 RWrist, 5 LShoulder, 6 LElbow, 7 LWrist, 8 MidHip, 9 RHip, 10 RKnee, 11 RAnkle, 12 LHip, 13 LKnee, 14 LAnkle, 15 REye, 16 LEye, 17 REar, 18 LEar, 19 LBigToe, 20 LSmallToe, 21 LHeel, 22 RBigToe, 23 RSmallToe, 24 RHeel. The same map also lists 25 Background, which the source excludes from the body-part count.

Which pose models output OpenPose BODY_25 body parts?

OpenPose BODY_25 model: OpenPose output format doc (02_output.md) says “Pose Output Format (BODY_25)”. Only models a fetched source ties to this scheme are listed.

How do OpenPose BODY_25 body parts map to other pose keypoint schemes?

By name only. 18 of the 25 share an identical name, once lowercased with separators removed, with a point in BlazePose 33, ML Kit 33, COCO 17, Halpe26, COCO-WholeBody 133, OpenPose COCO 18 and Apple Vision 2D; 8 MidHip, 19 LBigToe, 20 LSmallToe, 21 LHeel, 22 RBigToe, 23 RSmallToe and 24 RHeel do not and stay unmapped. A shared row means the names match, not that two models place the point in the same spot.

What coordinates come with OpenPose BODY_25 body parts?

In the sources' words: “The coordinates x and y can be normalized to the range [0,1], [-1,1], [0, source size], [0, output size], etc. (see the flag --keypoint_scale for more information), while the confidence score (c) in the range [0,1].” (OpenPose output format doc (02_output.md)).

Sources

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