diff --git a/api.go b/api.go
index f6dccad..95932f3 100644
--- a/api.go
+++ b/api.go
@@ -67,7 +67,7 @@ func NewApi(config ApiConfig) (*Api, error) {
 		return nil, fmt.Errorf("auth token request failed: %s", authTokenResponse.Message)
 	}
 
-	api.expiration = time.Now().Add(time.Duration(authTokenResponse.Result.ExpiresIn-1) * time.Second)
+	api.expiration = time.Now().Add(time.Duration(authTokenResponse.Result.ExpiresIn) * time.Second)
 	api.accessToken = authTokenResponse.Result.AccessToken
 	api.refreshToken = authTokenResponse.Result.RefreshToken
 
@@ -166,12 +166,18 @@ func (api *Api) AuthToken(authCode string) (*model.AuthTokenResponse, error) {
 	return response, nil
 }
 
-func (api *Api) AutoRefresh(ctx context.Context) error {
+func (api *Api) MustAutoRefresh(ctx context.Context, refreshBeforeExpiration time.Duration) {
+	if err := api.AutoRefresh(ctx, refreshBeforeExpiration); err != nil {
+		panic(err)
+	}
+}
+
+func (api *Api) AutoRefresh(ctx context.Context, refreshBeforeExpiration time.Duration) error {
 	for {
 		select {
 		case <-ctx.Done():
 			return nil
-		case <-time.After(time.Until(api.expiration)):
+		case <-time.After(time.Until(api.expiration.Add(-refreshBeforeExpiration))):
 			if err := api.Refresh(); err != nil {
 				return err
 			}
@@ -206,7 +212,7 @@ func (api *Api) Refresh() error {
 		return err
 	}
 
-	api.expiration = time.Now().Add(time.Duration(response.Result.ExpiresIn-1) * time.Second)
+	api.expiration = time.Now().Add(time.Duration(response.Result.ExpiresIn) * time.Second)
 	api.accessToken = response.Result.AccessToken
 	api.refreshToken = response.Result.RefreshToken