diff --git a/src/index.ts b/src/index.ts
index 40dee9b7..4ff3afee 100755
--- a/src/index.ts
+++ b/src/index.ts
@@ -8,7 +8,7 @@ import type {
   ReadDirItem,
   StatResult,
   DownloadFileOptions,
-  DownloadResult,
+  DownloadFileResult,
   Encoding,
   EncodingOrOptions,
   ProcessedOptions,
@@ -52,7 +52,7 @@ function parseOptions(encodingOrOptions?: EncodingOrOptions): ProcessedOptions {
   return options;
 }
 
-function encodeContents(contents: string, encoding: Encoding) {
+function encodeContents(contents: string, encoding: Encoding): string {
   if (encoding === 'utf8') {
     return btoa(encode_utf8(contents));
   }
@@ -68,7 +68,7 @@ function encodeContents(contents: string, encoding: Encoding) {
   throw new Error('Invalid encoding type "' + String(encoding) + '"');
 }
 
-function decodeContents(b64: string, encoding: Encoding) {
+function decodeContents(b64: string, encoding: Encoding): string {
   if (encoding === 'utf8') {
     return atob(decode_utf8(b64));
   }
@@ -208,10 +208,7 @@ export default {
     return RNFSManager.write(normalizeFilePath(filepath), b64, position).then(() => void 0);
   },
 
-  downloadFile(options: DownloadFileOptions): {
-    jobId: number;
-    promise: Promise<DownloadResult>;
-  } {
+  downloadFile(options: DownloadFileOptions): DownloadFileResult {
     const jobId = getJobId();
     let subscriptions: EmitterSubscription[] = [];
 
diff --git a/src/types.ts b/src/types.ts
index fd5ffda8..32d94d89 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -51,24 +51,29 @@ export type DownloadFileOptions = {
 };
 
 export type DownloadBeginCallbackResult = {
-  jobId: number; // The download job ID, required if one wishes to cancel the download. See `stopDownload`.
+  jobId: number; // The download jobId, required if one wishes to cancel the download. See `stopDownload`.
   statusCode: number; // The HTTP status code
   contentLength: number; // The total size in bytes of the download resource
   headers: Headers; // The HTTP response headers from the server
 };
 
 export type DownloadProgressCallbackResult = {
-  jobId: number; // The download job ID, required if one wishes to cancel the download. See `stopDownload`.
+  jobId: number; // The download jobId, required if one wishes to cancel the download. See `stopDownload`.
   contentLength: number; // The total size in bytes of the download resource
   bytesWritten: number; // The number of bytes written to the file so far
 };
 
 export type DownloadResult = {
-  jobId: number; // The download job ID, required if one wishes to cancel the download. See `stopDownload`.
+  jobId: number; // The download jobId, required if one wishes to cancel the download. See `stopDownload`.
   statusCode: number; // The HTTP status code
   bytesWritten: number; // The number of bytes written to the file
 };
 
+export type DownloadFileResult = {
+  jobId: number;
+  promise: Promise<DownloadResult>;
+};
+
 export type FSInfoResult = {
   totalSpace: number; // The total amount of storage space on the device (in bytes).
   freeSpace: number; // The amount of available storage space on the device (in bytes).