diff --git a/README.md b/README.md
index 2b1f499..7f9eee1 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ App can be called directly and do management in console.
 - `peertube-instance-index-filter -command index -url https://instances.joinpeertube.org/api/v1/instances/hosts -instance-url https://instances.joinpeertube.org/api/v1/instances` - add url to index of hosts. Later it will be used to collect instances
 - `peertube-instance-index-filter -command collect` - collect instances from index of hosts urls
 - `peertube-instance-index-filter -command reject -host www.example.com` - reject instance from index to exclude it from global index
-- `peertube-instance-index-filter -command audit -filter dead` - go through not rejected instances and check by filters: dead
+- `peertube-instance-index-filter -command audit -filter dead` - go through not rejected instances and check by filters: dead, duplicates
 
 ## Links
 
diff --git a/audit.go b/audit.go
index 6fee428..7a68a39 100644
--- a/audit.go
+++ b/audit.go
@@ -16,7 +16,10 @@
 
 package main
 
-import "net/http"
+import (
+	"fmt"
+	"net/http"
+)
 
 func doAudit(host string, filter string) bool {
 	switch filter {
@@ -29,3 +32,25 @@ func doAudit(host string, filter string) bool {
 
 	return false
 }
+
+func removeDuplicates() {
+	db := connectDB()
+	defer db.Close()
+
+	for {
+		ids, err := getDuplicateIds(db)
+		if err != nil {
+			panic(err)
+		}
+
+		if len(ids) == 0 {
+			break
+		}
+
+		fmt.Println("Removing duplicates:", len(ids), ids)
+
+		for _, id := range ids {
+			removeInstance(db, id)
+		}
+	}
+}
diff --git a/db.go b/db.go
index 33ca177..e897088 100644
--- a/db.go
+++ b/db.go
@@ -210,3 +210,24 @@ func getRejectedHostsTotal(db *sql.DB) (int, error) {
 
 	return totali, nil
 }
+
+func getDuplicateIds(db *sql.DB) ([]string, error) {
+	ids := []string{}
+	query := "SELECT id FROM instances GROUP BY url HAVING COUNT(*) > 1"
+	rows, err := db.Query(query)
+	if err != nil {
+		return ids, err
+	}
+
+	for rows.Next() {
+		var id string
+		rows.Scan(&id)
+		ids = append(ids, id)
+	}
+
+	return ids, nil
+}
+
+func removeInstance(db *sql.DB, id string) {
+	db.Exec("DELETE FROM instances WHERE id = ?", id)
+}
diff --git a/main.go b/main.go
index 772f43f..01911ff 100644
--- a/main.go
+++ b/main.go
@@ -148,6 +148,11 @@ func audit(filter string) {
 	db := connectDB()
 	defer db.Close()
 
+	if filter == "duplicates" {
+		removeDuplicates()
+		return
+	}
+
 	hosts, err := getHosts(db, 0, 10000, "", "", "url")
 	if err != nil {
 		panic(err)