diff --git a/app/vmagent/main.go b/app/vmagent/main.go
index 8e46d4624..7079c6b08 100644
--- a/app/vmagent/main.go
+++ b/app/vmagent/main.go
@@ -236,26 +236,26 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 			return true
 		}
 		// See https://docs.datadoghq.com/api/latest/metrics/#submit-metrics
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(202)
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "/datadog/api/v1/validate":
 		datadogValidateRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/authentication/#validate-api-key
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{"valid":true}`)
 		return true
 	case "/datadog/api/v1/check_run":
 		datadogCheckRunRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/service-checks/#submit-a-service-check
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(202)
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "/datadog/intake/":
 		datadogIntakeRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{}`)
 		return true
 	case "/targets":
@@ -277,7 +277,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 		return true
 	case "/api/v1/targets":
 		promscrapeAPIV1TargetsRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		state := r.FormValue("state")
 		promscrape.WriteAPIV1Targets(w, state)
 		return true
@@ -391,19 +391,19 @@ func processMultitenantRequest(w http.ResponseWriter, r *http.Request, path stri
 	case "datadog/api/v1/validate":
 		datadogValidateRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/authentication/#validate-api-key
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{"valid":true}`)
 		return true
 	case "datadog/api/v1/check_run":
 		datadogCheckRunRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/service-checks/#submit-a-service-check
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(202)
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "datadog/intake/":
 		datadogIntakeRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{}`)
 		return true
 	default:
diff --git a/app/vmalert/datasource/vm.go b/app/vmalert/datasource/vm.go
index 304d88cec..c900ed2f6 100644
--- a/app/vmalert/datasource/vm.go
+++ b/app/vmalert/datasource/vm.go
@@ -150,7 +150,7 @@ func (s *VMStorage) newRequestPOST() (*http.Request, error) {
 	if err != nil {
 		return nil, err
 	}
-	req.Header.Set("Content-Type", "application/json; charset=utf-8")
+	req.Header.Set("Content-Type", "application/json")
 	if s.authCfg != nil {
 		if auth := s.authCfg.GetAuthHeader(); auth != "" {
 			req.Header.Set("Authorization", auth)
diff --git a/app/vmalert/notifier/alertmanager.go b/app/vmalert/notifier/alertmanager.go
index 36b75cfbb..cf132f828 100644
--- a/app/vmalert/notifier/alertmanager.go
+++ b/app/vmalert/notifier/alertmanager.go
@@ -32,7 +32,7 @@ func (am *AlertManager) Send(ctx context.Context, alerts []Alert) error {
 	if err != nil {
 		return err
 	}
-	req.Header.Set("Content-Type", "application/json; charset=utf-8")
+	req.Header.Set("Content-Type", "application/json")
 	req = req.WithContext(ctx)
 	if am.basicAuthPass != "" {
 		req.SetBasicAuth(am.basicAuthUser, am.basicAuthPass)
diff --git a/app/vmalert/web.go b/app/vmalert/web.go
index e1034dab7..5100d0e36 100644
--- a/app/vmalert/web.go
+++ b/app/vmalert/web.go
@@ -68,7 +68,7 @@ func (rh *requestHandler) handler(w http.ResponseWriter, r *http.Request) bool {
 			httpserver.Errorf(w, r, "%s", err)
 			return true
 		}
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.Write(data)
 		return true
 	case "/api/v1/alerts":
@@ -77,7 +77,7 @@ func (rh *requestHandler) handler(w http.ResponseWriter, r *http.Request) bool {
 			httpserver.Errorf(w, r, "%s", err)
 			return true
 		}
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.Write(data)
 		return true
 	case "/-/reload":
@@ -102,7 +102,7 @@ func (rh *requestHandler) handler(w http.ResponseWriter, r *http.Request) bool {
 				httpserver.Errorf(w, r, "failed to marshal alert: %s", err)
 				return true
 			}
-			w.Header().Set("Content-Type", "application/json; charset=utf-8")
+			w.Header().Set("Content-Type", "application/json")
 			w.Write(data)
 			return true
 		}
diff --git a/app/vminsert/main.go b/app/vminsert/main.go
index fdf137249..a16dbceaf 100644
--- a/app/vminsert/main.go
+++ b/app/vminsert/main.go
@@ -254,26 +254,26 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 			return true
 		}
 		// See https://docs.datadoghq.com/api/latest/metrics/#submit-metrics
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(202)
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "datadog/api/v1/validate":
 		datadogValidateRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/authentication/#validate-api-key
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{"valid":true}`)
 		return true
 	case "datadog/api/v1/check_run":
 		datadogCheckRunRequests.Inc()
 		// See https://docs.datadoghq.com/api/latest/service-checks/#submit-a-service-check
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		w.WriteHeader(202)
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "datadog/intake/":
 		datadogIntakeRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, `{}`)
 		return true
 	default:
diff --git a/app/vmselect/graphite/metrics_api.go b/app/vmselect/graphite/metrics_api.go
index 465dff496..6f2ac5f76 100644
--- a/app/vmselect/graphite/metrics_api.go
+++ b/app/vmselect/graphite/metrics_api.go
@@ -468,7 +468,7 @@ const maxRegexpCacheSize = 10000
 
 func getContentType(jsonp string) string {
 	if jsonp == "" {
-		return "application/json; charset=utf-8"
+		return "application/json"
 	}
 	return "text/javascript; charset=utf-8"
 }
diff --git a/app/vmselect/graphite/tags_api.go b/app/vmselect/graphite/tags_api.go
index 4d3a87da8..ffe5cc7a7 100644
--- a/app/vmselect/graphite/tags_api.go
+++ b/app/vmselect/graphite/tags_api.go
@@ -62,7 +62,7 @@ func TagsDelSeriesHandler(startTime time.Time, at *auth.Token, w http.ResponseWr
 		totalDeleted += n
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	if totalDeleted > 0 {
 		fmt.Fprintf(w, "true")
 	} else {
@@ -142,7 +142,7 @@ func registerMetrics(startTime time.Time, at *auth.Token, w http.ResponseWriter,
 	// Return response
 	contentType := "text/plain; charset=utf-8"
 	if isJSONResponse {
-		contentType = "application/json; charset=utf-8"
+		contentType = "application/json"
 	}
 	w.Header().Set("Content-Type", contentType)
 	WriteTagsTagMultiSeriesResponse(w, canonicalPaths, isJSONResponse)
@@ -370,7 +370,7 @@ func TagsFindSeriesHandler(startTime time.Time, at *auth.Token, w http.ResponseW
 		paths = paths[:limit]
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteTagsFindSeriesResponse(bw, isPartial, paths)
@@ -427,7 +427,7 @@ func TagValuesHandler(startTime time.Time, at *auth.Token, tagName string, w htt
 		return err
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteTagValuesResponse(bw, isPartial, tagName, tagValues)
@@ -459,7 +459,7 @@ func TagsHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r *
 		return err
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteTagsResponse(bw, isPartial, labels)
diff --git a/app/vmselect/main.go b/app/vmselect/main.go
index 27aee9f7c..9f4d82eda 100644
--- a/app/vmselect/main.go
+++ b/app/vmselect/main.go
@@ -305,7 +305,7 @@ func selectHandler(startTime time.Time, w http.ResponseWriter, r *http.Request,
 	}
 	if strings.HasPrefix(p.Suffix, "graphite/functions") {
 		graphiteFunctionsRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, "%s", `{}`)
 		return true
 	}
@@ -505,25 +505,25 @@ func selectHandler(startTime time.Time, w http.ResponseWriter, r *http.Request,
 	case "prometheus/api/v1/rules", "prometheus/rules":
 		// Return dumb placeholder for https://prometheus.io/docs/prometheus/latest/querying/api/#rules
 		rulesRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, "%s", `{"status":"success","data":{"groups":[]}}`)
 		return true
 	case "prometheus/api/v1/alerts", "prometheus/alerts":
 		// Return dumb placeholder for https://prometheus.io/docs/prometheus/latest/querying/api/#alerts
 		alertsRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, "%s", `{"status":"success","data":{"alerts":[]}}`)
 		return true
 	case "prometheus/api/v1/metadata":
 		// Return dumb placeholder for https://prometheus.io/docs/prometheus/latest/querying/api/#querying-metric-metadata
 		metadataRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, "%s", `{"status":"success","data":{}}`)
 		return true
 	case "prometheus/api/v1/query_exemplars":
 		// Return dumb placeholder for https://prometheus.io/docs/prometheus/latest/querying/api/#querying-exemplars
 		queryExemplarsRequests.Inc()
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		fmt.Fprintf(w, "%s", `{"status":"success","data":null}`)
 		return true
 	default:
@@ -562,7 +562,7 @@ func isGraphiteTagsPath(path string) bool {
 func sendPrometheusError(w http.ResponseWriter, r *http.Request, err error) {
 	logger.Warnf("error in %q: %s", httpserver.GetRequestURI(r), err)
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	statusCode := http.StatusUnprocessableEntity
 	var esc *httpserver.ErrorWithStatusCode
 	if errors.As(err, &esc) {
diff --git a/app/vmselect/prometheus/prometheus.go b/app/vmselect/prometheus/prometheus.go
index c9303a4fa..2c63cc10d 100644
--- a/app/vmselect/prometheus/prometheus.go
+++ b/app/vmselect/prometheus/prometheus.go
@@ -590,7 +590,7 @@ func LabelValuesHandler(startTime time.Time, at *auth.Token, labelName string, w
 		}
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteLabelValuesResponse(bw, isPartial, labelValues)
@@ -685,7 +685,7 @@ func LabelsCountHandler(startTime time.Time, at *auth.Token, w http.ResponseWrit
 		return fmt.Errorf(`cannot obtain label entries: %w`, err)
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteLabelsCountResponse(bw, isPartial, labelEntries)
@@ -756,7 +756,7 @@ func TSDBStatusHandler(startTime time.Time, at *auth.Token, w http.ResponseWrite
 		}
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteTSDBStatusResponse(bw, isPartial, status)
@@ -852,7 +852,7 @@ func LabelsHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r
 		}
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteLabelsResponse(bw, isPartial, labels)
@@ -933,7 +933,7 @@ func SeriesCountHandler(startTime time.Time, at *auth.Token, w http.ResponseWrit
 		return fmt.Errorf("cannot obtain series count: %w", err)
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteSeriesCountResponse(bw, isPartial, n)
@@ -985,7 +985,7 @@ func SeriesHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r
 		if err != nil {
 			return fmt.Errorf("cannot fetch time series for %q: %w", sq, err)
 		}
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		bw := bufferedwriter.Get(w)
 		defer bufferedwriter.Put(bw)
 		resultsCh := make(chan *quicktemplate.ByteBuffer)
@@ -1010,7 +1010,7 @@ func SeriesHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r
 		return fmt.Errorf("cannot fetch data for %q: %w", sq, err)
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	resultsCh := make(chan *quicktemplate.ByteBuffer)
@@ -1147,7 +1147,7 @@ func QueryHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r
 		}
 	}
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteQueryResponse(bw, ec.IsPartialResponse, result)
@@ -1243,7 +1243,7 @@ func queryRangeHandler(startTime time.Time, at *auth.Token, w http.ResponseWrite
 	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/153
 	result = removeEmptyValuesAndTimeseries(result)
 
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	WriteQueryRangeResponse(bw, ec.IsPartialResponse, result)
@@ -1423,7 +1423,7 @@ func QueryStatsHandler(startTime time.Time, at *auth.Token, w http.ResponseWrite
 		return fmt.Errorf("cannot parse `maxLifetime` arg: %w", err)
 	}
 	maxLifetime := time.Duration(maxLifetimeMsecs) * time.Millisecond
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
 	if at == nil {
diff --git a/app/vmstorage/main.go b/app/vmstorage/main.go
index a9bb2a43c..1939d6ed2 100644
--- a/app/vmstorage/main.go
+++ b/app/vmstorage/main.go
@@ -182,7 +182,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request, strg *storage.Storag
 
 	switch path {
 	case "/create":
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		snapshotPath, err := strg.CreateSnapshot()
 		if err != nil {
 			err = fmt.Errorf("cannot create snapshot: %w", err)
@@ -192,7 +192,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request, strg *storage.Storag
 		fmt.Fprintf(w, `{"status":"ok","snapshot":%q}`, snapshotPath)
 		return true
 	case "/list":
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		snapshots, err := strg.ListSnapshots()
 		if err != nil {
 			err = fmt.Errorf("cannot list snapshots: %w", err)
@@ -209,7 +209,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request, strg *storage.Storag
 		fmt.Fprintf(w, `]}`)
 		return true
 	case "/delete":
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		snapshotName := r.FormValue("snapshot")
 		if err := strg.DeleteSnapshot(snapshotName); err != nil {
 			err = fmt.Errorf("cannot delete snapshot %q: %w", snapshotName, err)
@@ -219,7 +219,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request, strg *storage.Storag
 		fmt.Fprintf(w, `{"status":"ok"}`)
 		return true
 	case "/delete_all":
-		w.Header().Set("Content-Type", "application/json; charset=utf-8")
+		w.Header().Set("Content-Type", "application/json")
 		snapshots, err := strg.ListSnapshots()
 		if err != nil {
 			err = fmt.Errorf("cannot list snapshots: %w", err)
diff --git a/lib/influxutils/influxutils.go b/lib/influxutils/influxutils.go
index f441ddd49..0350b0102 100644
--- a/lib/influxutils/influxutils.go
+++ b/lib/influxutils/influxutils.go
@@ -16,7 +16,7 @@ func WriteDatabaseNames(w http.ResponseWriter) {
 	// Emulate fake response for influx query.
 	// This is required for TSBS benchmark and some Telegraf plugins.
 	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1124
-	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("Content-Type", "application/json")
 	dbNames := *influxDatabaseNames
 	if len(dbNames) == 0 {
 		dbNames = []string{"_internal"}