@@ -459,6 +459,7 @@ func (ir *imageRouter) getImagesJSON(ctx context.Context, w http.ResponseWriter,

 	useNone := versions.LessThan(version, "1.43")

 	withVirtualSize := versions.LessThan(version, "1.44")

 	noDescriptor := versions.LessThan(version, "1.48")

+	noContainers := versions.LessThan(version, "1.51")

 	for _, img := range images {

 		if useNone {

 			if len(img.RepoTags) == 0 && len(img.RepoDigests) == 0 {

@@ -479,6 +480,9 @@ func (ir *imageRouter) getImagesJSON(ctx context.Context, w http.ResponseWriter,

 		if noDescriptor {

 			img.Descriptor = nil

 		}

+		if noContainers {

+			img.Containers = -1

+		}

 	}

 	return httputils.WriteJSON(w, http.StatusOK, images)

@@ -2196,8 +2196,7 @@ definitions:

           Number of containers using this image. Includes both stopped and running

           containers.

-          This size is not calculated by default, and depends on which API endpoint

-          is used. `-1` indicates that the value has not been set / calculated.

+          `-1` indicates that the value has not been set / calculated.

         x-nullable: false

         type: "integer"

         example: 2

@@ -75,6 +75,8 @@ type ListOptions struct {

 	SharedSize bool

 	// ContainerCount indicates whether container count should be computed.

+	//

+	// Deprecated: This field has been unused and is no longer required and will be removed in a future version.

 	ContainerCount bool

 	// Manifests indicates whether the image manifests should be returned.

@@ -409,10 +409,7 @@ func (i *ImageService) imageSummary(ctx context.Context, img c8dimages.Image, pl

 	image.Manifests = summary.Manifests

 	target := img.Target

 	image.Descriptor = &target

-

-	if opts.ContainerCount {

-		image.Containers = summary.ContainersCount

-	}

+	image.Containers = summary.ContainersCount

 	return image, summary, nil

 }

@@ -57,9 +57,8 @@ func (daemon *Daemon) imageDiskUsage(ctx context.Context) ([]*image.Summary, err

 	imgs, _, err := daemon.usageImages.Do(ctx, struct{}{}, func(ctx context.Context) ([]*image.Summary, error) {

 		// Get all top images with extra attributes

 		imgs, err := daemon.imageService.Images(ctx, image.ListOptions{

-			Filters:        filters.NewArgs(),

-			SharedSize:     true,

-			ContainerCount: true,

+			Filters:    filters.NewArgs(),

+			SharedSize: true,

 		})

 		if err != nil {

 			return nil, errors.Wrap(err, "failed to retrieve image list")

@@ -105,7 +105,7 @@ func (i *ImageService) Images(ctx context.Context, opts imagetypes.ListOptions)

 	var (

 		summaries     = make([]*imagetypes.Summary, 0, len(selectedImages))

-		summaryMap    map[*image.Image]*imagetypes.Summary

+		summaryMap    = make(map[*image.Image]*imagetypes.Summary, len(selectedImages))

 		allContainers []*container.Container

 	)

 	for id, img := range selectedImages {

@@ -198,30 +198,20 @@ func (i *ImageService) Images(ctx context.Context, opts imagetypes.ListOptions)

 			continue

 		}

-		if opts.ContainerCount {

-			// Lazily init allContainers.

-			if allContainers == nil {

-				allContainers = i.containers.List()

-			}

-

-			// Get container count

-			var containers int64

-			for _, c := range allContainers {

-				if c.ImageID == id {

-					containers++

-				}

-			}

-			// NOTE: By default, Containers is -1, or "not set"

-			summary.Containers = containers

+		// Lazily init allContainers.

+		if allContainers == nil {

+			allContainers = i.containers.List()

 		}

-		if opts.ContainerCount || opts.SharedSize {

-			// Lazily init summaryMap.

-			if summaryMap == nil {

-				summaryMap = make(map[*image.Image]*imagetypes.Summary, len(selectedImages))

+		// Get container count

+		var containersCount int64

+		for _, c := range allContainers {

+			if c.ImageID == id {

+				containersCount++

 			}

-			summaryMap[img] = summary

 		}

+		summary.Containers = containersCount

+		summaryMap[img] = summary

 		summaries = append(summaries, summary)

 	}

@@ -17,6 +17,9 @@ keywords: "API, Docker, rcli, REST, documentation"

 [Docker Engine API v1.51](https://docs.docker.com/reference/api/engine/version/v1.51/) documentation

+* `GET /images/json` now sets the value of `Containers` field for all images

+  to the count of containers using the image.

+  This field was previously always -1.

 ## v1.50 API changes