diff --git a/imaginary.go b/imaginary.go
index b2d972a..f9c1e84 100644
--- a/imaginary.go
+++ b/imaginary.go
@@ -38,7 +38,7 @@ var (
 	aCertFile           = flag.String("certfile", "", "TLS certificate file path")
 	aKeyFile            = flag.String("keyfile", "", "TLS private key file path")
 	aAuthorization      = flag.String("authorization", "", "Defines a constant Authorization header value passed to all the image source servers. -enable-url-source flag must be defined. This overwrites authorization headers forwarding behavior via X-Forward-Authorization")
-	aCustomHeaders      = flag.String("forward-headers", "", "Forwards custom headers to the image source server. -enable-url-source flag must be defined.")
+	aForwardHeaders     = flag.String("forward-headers", "", "Forwards custom headers to the image source server. -enable-url-source flag must be defined.")
 	aPlaceholder        = flag.String("placeholder", "", "Image path to image custom placeholder to be used in case of error. Recommended minimum image size is: 1200x1200")
 	aDisableEndpoints   = flag.String("disable-endpoints", "", "Comma separated endpoints to disable. E.g: form,crop,rotate,health")
 	aHTTPCacheTTL       = flag.Int("http-cache-ttl", -1, "The TTL in seconds")
@@ -146,7 +146,7 @@ func main() {
 		HTTPReadTimeout:    *aReadTimeout,
 		HTTPWriteTimeout:   *aWriteTimeout,
 		Authorization:      *aAuthorization,
-		CustomHeaders:      parseCustomHeaders(*aCustomHeaders),
+		ForwardHeaders:     parseForwardHeaders(*aForwardHeaders),
 		AllowedOrigins:     parseOrigins(*aAllowedOrigins),
 		MaxAllowedSize:     *aMaxAllowedSize,
 	}
@@ -268,14 +268,14 @@ func checkHTTPCacheTTL(ttl int) {
 	}
 }
 
-func parseCustomHeaders(customHeaders string) []string {
+func parseForwardHeaders(forwardHeaders string) []string {
 	var headers []string
-	if customHeaders == "" {
+	if forwardHeaders == "" {
 		return headers
 	}
-	for _, header := range strings.Split(customHeaders, ",") {
+	for _, header := range strings.Split(forwardHeaders, ",") {
 		if header != "" {
-			headers = append(headers, header)
+			headers = append(headers, strings.TrimSpace(header))
 		}
 	}
 	return headers
diff --git a/server.go b/server.go
index 63d466f..6e35ca9 100644
--- a/server.go
+++ b/server.go
@@ -33,7 +33,7 @@ type ServerOptions struct {
 	KeyFile            string
 	Authorization      string
 	Placeholder        string
-	CustomHeaders      []string
+	ForwardHeaders     []string
 	PlaceholderImage   []byte
 	Endpoints          Endpoints
 	AllowedOrigins     []*url.URL
diff --git a/source.go b/source.go
index 03d3af8..572e6aa 100644
--- a/source.go
+++ b/source.go
@@ -13,7 +13,7 @@ type SourceConfig struct {
 	Authorization  string
 	MountPath      string
 	Type           ImageSourceType
-	CustomHeaders  []string
+	ForwardHeaders []string
 	AllowedOrigins []*url.URL
 	MaxAllowedSize int
 }
@@ -39,7 +39,7 @@ func LoadSources(o ServerOptions) {
 			Authorization:  o.Authorization,
 			AllowedOrigins: o.AllowedOrigins,
 			MaxAllowedSize: o.MaxAllowedSize,
-			CustomHeaders:  o.CustomHeaders,
+			ForwardHeaders: o.ForwardHeaders,
 		})
 	}
 }
diff --git a/source_http.go b/source_http.go
index 947b9a2..c3840e2 100644
--- a/source_http.go
+++ b/source_http.go
@@ -86,8 +86,8 @@ func (s *HTTPImageSource) setAuthorizationHeader(req *http.Request, ireq *http.R
 	}
 }
 
-func (s *HTTPImageSource) setCustomHeaders(req *http.Request, ireq *http.Request) {
-	headers := s.Config.CustomHeaders
+func (s *HTTPImageSource) setForwardHeaders(req *http.Request, ireq *http.Request) {
+	headers := s.Config.ForwardHeaders
 	for _, header := range headers {
 		if header != "" && ireq.Header.Get(header) != "" && req.Header.Get(header) == "" {
 			req.Header.Set(header, ireq.Header.Get(header))
@@ -104,8 +104,8 @@ func newHTTPRequest(s *HTTPImageSource, ireq *http.Request, method string, url *
 	req.Header.Set("User-Agent", "imaginary/"+Version)
 	req.URL = url
 
-	if len(s.Config.CustomHeaders) != 0 {
-		s.setCustomHeaders(req, ireq)
+	if len(s.Config.ForwardHeaders) != 0 {
+		s.setForwardHeaders(req, ireq)
 	}
 
 	// Forward auth header to the target server, if necessary
diff --git a/source_http_test.go b/source_http_test.go
index 1620279..e558065 100755
--- a/source_http_test.go
+++ b/source_http_test.go
@@ -134,13 +134,13 @@ func TestHttpImageSourceForwardHeaders(t *testing.T) {
 		r, _ := http.NewRequest(http.MethodGet, "http://foo/bar?url=http://bar.com", nil)
 		r.Header.Set(header, "foobar")
 
-		source := &HTTPImageSource{&SourceConfig{CustomHeaders: cases}}
+		source := &HTTPImageSource{&SourceConfig{ForwardHeaders: cases}}
 		if !source.Matches(r) {
 			t.Fatal("Cannot match the request")
 		}
 
 		oreq := &http.Request{Header: make(http.Header)}
-		source.setCustomHeaders(oreq, r)
+		source.setForwardHeaders(oreq, r)
 
 		if oreq.Header.Get(header) != "foobar" {
 			t.Fatal("Missmatch custom header")
@@ -159,7 +159,7 @@ func TestHttpImageSourceNotForwardHeaders(t *testing.T) {
 	r, _ := http.NewRequest(http.MethodGet, "http://foo/bar?url="+url.String(), nil)
 	r.Header.Set("Not-Forward", "foobar")
 
-	source := &HTTPImageSource{&SourceConfig{CustomHeaders: cases}}
+	source := &HTTPImageSource{&SourceConfig{ForwardHeaders: cases}}
 	if !source.Matches(r) {
 		t.Fatal("Cannot match the request")
 	}
@@ -182,7 +182,7 @@ func TestHttpImageSourceForwardedHeadersNotOverride(t *testing.T) {
 	r, _ := http.NewRequest(http.MethodGet, "http://foo/bar?url="+url.String() , nil)
 	r.Header.Set("Authorization", "foobar")
 	
-	source := &HTTPImageSource{&SourceConfig{Authorization: "ValidAPIKey", CustomHeaders: cases}}
+	source := &HTTPImageSource{&SourceConfig{Authorization: "ValidAPIKey", ForwardHeaders: cases}}
 	if !source.Matches(r) {
 		t.Fatal("Cannot match the request")
 	}
@@ -205,7 +205,7 @@ func TestHttpImageSourceCaseSensitivityInForwardedHeaders(t *testing.T) {
 	r, _ := http.NewRequest(http.MethodGet, "http://foo/bar?url="+url.String(), nil)
 	r.Header.Set("x-custom", "foobar")
 
-	source := &HTTPImageSource{&SourceConfig{CustomHeaders: cases}}
+	source := &HTTPImageSource{&SourceConfig{ForwardHeaders: cases}}
 	if !source.Matches(r) {
 		t.Fatal("Cannot match the request")
 	}
@@ -224,13 +224,13 @@ func TestHttpImageSourceEmptyForwardedHeaders(t *testing.T) {
 
 	r, _ := http.NewRequest(http.MethodGet, "http://foo/bar?url="+url.String(), nil)
 
-	source := &HTTPImageSource{&SourceConfig{CustomHeaders: cases}}
+	source := &HTTPImageSource{&SourceConfig{ForwardHeaders: cases}}
 	if !source.Matches(r) {
 		t.Fatal("Cannot match the request")
 	}
 
-	if len(source.Config.CustomHeaders) != 0 {
-		t.Log(source.Config.CustomHeaders)
+	if len(source.Config.ForwardHeaders) != 0 {
+		t.Log(source.Config.ForwardHeaders)
 		t.Fatal("Setted empty custom header")
 	}