diff --git a/cli/api.go b/cli/api.go
index 806d109..0d1ac5c 100644
--- a/cli/api.go
+++ b/cli/api.go
@@ -242,6 +242,8 @@ var validFormats = map[string]bool{
 	"detailed":      true,
 	"summary-html":  true,
 	"detailed-html": true,
+	"summary-json":  true,
+	"detailed-json": true,
 }
 
 // runTrack handles the track command execution
diff --git a/engine/tracker/helpers.go b/engine/tracker/helpers.go
index a681a34..a37f90e 100644
--- a/engine/tracker/helpers.go
+++ b/engine/tracker/helpers.go
@@ -52,20 +52,12 @@ func DetectChange(baseline, current *parser.LineObj) (*FunctionChangeResult, err
 		ChangeType:        changeType,
 		FlatChangePercent: flatChange,
 		CumChangePercent:  cumChange,
-		FlatAbsolute: struct {
-			Before float64
-			After  float64
-			Delta  float64
-		}{
+		FlatAbsolute: AbsoluteChange{
 			Before: baseline.Flat,
 			After:  current.Flat,
 			Delta:  current.Flat - baseline.Flat,
 		},
-		CumAbsolute: struct {
-			Before float64
-			After  float64
-			Delta  float64
-		}{
+		CumAbsolute: AbsoluteChange{
 			Before: baseline.Cum,
 			After:  current.Cum,
 			Delta:  current.Cum - baseline.Cum,
diff --git a/engine/tracker/profile_change_report.go b/engine/tracker/profile_change_report.go
index a8e686d..d1df303 100644
--- a/engine/tracker/profile_change_report.go
+++ b/engine/tracker/profile_change_report.go
@@ -1,6 +1,7 @@
 package tracker
 
 import (
+	"encoding/json"
 	"fmt"
 	"html/template"
 	"log/slog"
@@ -323,6 +324,126 @@ func (r *ProfileChangeReport) generateDetailedHTMLReport(outputPath string) erro
 	return t.Execute(file, data)
 }
 
+// JSON data structures
+type jsonSummaryData struct {
+	TotalFunctions int                     `json:"total_functions"`
+	Statistics     jsonStatistics          `json:"statistics"`
+	Regressions    []*FunctionChangeResult `json:"regressions"`
+	Improvements   []*FunctionChangeResult `json:"improvements"`
+}
+
+type jsonStatistics struct {
+	Regressions  int `json:"regressions"`
+	Improvements int `json:"improvements"`
+	Stable       int `json:"stable"`
+}
+
+type jsonDetailedData struct {
+	TotalFunctions int                     `json:"total_functions"`
+	Statistics     jsonStatistics          `json:"statistics"`
+	Changes        []*FunctionChangeResult `json:"changes"`
+	SortOrder      string                  `json:"sort_order"`
+}
+
+func (r *ProfileChangeReport) generateJSONSummary(outputPath string) error {
+	var regressionList, improvementList []*FunctionChangeResult
+	var stable int
+
+	for _, change := range r.FunctionChanges {
+		switch change.ChangeType {
+		case shared.REGRESSION:
+			regressionList = append(regressionList, change)
+		case shared.IMPROVEMENT:
+			improvementList = append(improvementList, change)
+		default:
+			stable++
+		}
+	}
+
+	// Sort regressions by percentage (biggest regression first)
+	sort.Slice(regressionList, func(i, j int) bool {
+		return regressionList[i].FlatChangePercent > regressionList[j].FlatChangePercent
+	})
+
+	// Sort improvements by absolute percentage (biggest improvement first)
+	sort.Slice(improvementList, func(i, j int) bool {
+		return math.Abs(improvementList[i].FlatChangePercent) > math.Abs(improvementList[j].FlatChangePercent)
+	})
+
+	data := jsonSummaryData{
+		TotalFunctions: len(r.FunctionChanges),
+		Statistics: jsonStatistics{
+			Regressions:  len(regressionList),
+			Improvements: len(improvementList),
+			Stable:       stable,
+		},
+		Regressions:  regressionList,
+		Improvements: improvementList,
+	}
+
+	file, err := os.Create(outputPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	encoder := json.NewEncoder(file)
+	encoder.SetIndent("", "  ")
+	return encoder.Encode(data)
+}
+
+func (r *ProfileChangeReport) generateDetailedJSONReport(outputPath string) error {
+	changes := r.FunctionChanges
+
+	// Count types
+	var regressions, improvements, stable int
+	for _, change := range changes {
+		switch change.ChangeType {
+		case shared.REGRESSION:
+			regressions++
+		case shared.IMPROVEMENT:
+			improvements++
+		default:
+			stable++
+		}
+	}
+
+	// Sort: regressions → improvements → stable, each by magnitude
+	typePriority := map[string]int{
+		shared.REGRESSION:  regressionPriority,
+		shared.IMPROVEMENT: improvementPriority,
+		shared.STABLE:      stablePriority,
+	}
+
+	sort.Slice(changes, func(i, j int) bool {
+		if typePriority[changes[i].ChangeType] != typePriority[changes[j].ChangeType] {
+			return typePriority[changes[i].ChangeType] < typePriority[changes[j].ChangeType]
+		}
+		return math.Abs(changes[i].FlatChangePercent) > math.Abs(changes[j].FlatChangePercent)
+	})
+
+	data := jsonDetailedData{
+		TotalFunctions: len(changes),
+		Statistics: jsonStatistics{
+			Regressions:  regressions,
+			Improvements: improvements,
+			Stable:       stable,
+		},
+		Changes:   changes,
+		SortOrder: "Regressions (worst → best), then Improvements (best → worst), then Stable",
+	}
+
+	file, err := os.Create(outputPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	encoder := json.NewEncoder(file)
+	encoder.SetIndent("", "  ")
+	return encoder.Encode(data)
+}
+
 func (r *ProfileChangeReport) ChooseOutputFormat(outputFormat string) {
 	switch outputFormat {
 	case "summary":
@@ -337,5 +458,13 @@ func (r *ProfileChangeReport) ChooseOutputFormat(outputFormat string) {
 		if err := r.generateDetailedHTMLReport("detailed.html"); err != nil {
 			slog.Info("detailed-html failed", "err", err)
 		}
+	case "summary-json":
+		if err := r.generateJSONSummary("summary.json"); err != nil {
+			slog.Info("summary-json failed", "err", err)
+		}
+	case "detailed-json":
+		if err := r.generateDetailedJSONReport("detailed.json"); err != nil {
+			slog.Info("detailed-json failed", "err", err)
+		}
 	}
 }
diff --git a/engine/tracker/types.go b/engine/tracker/types.go
index d679af0..c003dbe 100644
--- a/engine/tracker/types.go
+++ b/engine/tracker/types.go
@@ -8,20 +8,18 @@ type ProfileChangeReport struct {
 	FunctionChanges []*FunctionChangeResult
 }
 
+type AbsoluteChange struct {
+	Before float64 `json:"before"`
+	After  float64 `json:"after"`
+	Delta  float64 `json:"delta"`
+}
+
 type FunctionChangeResult struct {
-	FunctionName      string
-	ChangeType        string // shared.REGRESSION, shred.IMPROVEMENT, shared.STABLE
-	FlatChangePercent float64
-	CumChangePercent  float64
-	FlatAbsolute      struct {
-		Before float64
-		After  float64
-		Delta  float64
-	}
-	CumAbsolute struct {
-		Before float64
-		After  float64
-		Delta  float64
-	}
-	Timestamp time.Time
+	FunctionName      string         `json:"function_name"`
+	ChangeType        string         `json:"change_type"`
+	FlatChangePercent float64        `json:"flat_change_percent"`
+	CumChangePercent  float64        `json:"cum_change_percent"`
+	FlatAbsolute      AbsoluteChange `json:"flat_absolute"`
+	CumAbsolute       AbsoluteChange `json:"cum_absolute"`
+	Timestamp         time.Time      `json:"timestamp"`
 }
diff --git a/go.mod b/go.mod
index f6c38ae..85d28ff 100644
--- a/go.mod
+++ b/go.mod
@@ -2,13 +2,15 @@ module github.com/AlexsanderHamir/prof
 
 go 1.24.3
 
-require github.com/spf13/cobra v1.9.1
+require (
+	github.com/microcosm-cc/bluemonday v1.0.27
+	github.com/spf13/cobra v1.9.1
+)
 
 require (
 	github.com/aymerick/douceur v0.2.0 // indirect
 	github.com/gorilla/css v1.0.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
-	github.com/microcosm-cc/bluemonday v1.0.27 // indirect
 	github.com/spf13/pflag v1.0.7 // indirect
 	golang.org/x/net v0.26.0 // indirect
 )