diff --git a/Examples/SDWebImage Demo/MasterViewController.m b/Examples/SDWebImage Demo/MasterViewController.m
index 3a6c1780..f131f55f 100644
--- a/Examples/SDWebImage Demo/MasterViewController.m	
+++ b/Examples/SDWebImage Demo/MasterViewController.m	
@@ -115,7 +115,8 @@
     cell.customTextLabel.text = [NSString stringWithFormat:@"Image #%ld", (long)indexPath.row];
     [cell.customImageView sd_setImageWithURL:[NSURL URLWithString:self.objects[indexPath.row]]
                             placeholderImage:placeholderImage
-                                     options:indexPath.row == 0 ? SDWebImageRefreshCached : 0];
+                                     options:indexPath.row == 0 ? SDWebImageRefreshCached : 0
+                                     context:@{SDWebImageContextImageThumbnailPixelSize : @(CGSizeMake(180, 120))}];
     return cell;
 }
 
diff --git a/SDWebImage/Core/SDWebImageManager.m b/SDWebImage/Core/SDWebImageManager.m
index 61c0a36c..97ffb488 100644
--- a/SDWebImage/Core/SDWebImageManager.m
+++ b/SDWebImage/Core/SDWebImageManager.m
@@ -95,19 +95,45 @@ static id<SDImageLoader> _defaultImageLoader;
 }
 
 - (nullable NSString *)cacheKeyForURL:(nullable NSURL *)url {
-    return [self cacheKeyForURL:url cacheKeyFilter:self.cacheKeyFilter];
+    return [self cacheKeyForURL:url context:nil];
 }
 
-- (nullable NSString *)cacheKeyForURL:(nullable NSURL *)url cacheKeyFilter:(id<SDWebImageCacheKeyFilter>)cacheKeyFilter {
+- (nullable NSString *)cacheKeyForURL:(nullable NSURL *)url context:(nullable SDWebImageContext *)context {
     if (!url) {
         return @"";
     }
-
-    if (cacheKeyFilter) {
-        return [cacheKeyFilter cacheKeyForURL:url];
-    } else {
-        return url.absoluteString;
+    
+    NSString *key;
+    // Cache Key Filter
+    id<SDWebImageCacheKeyFilter> cacheKeyFilter = self.cacheKeyFilter;
+    if (context[SDWebImageContextCacheKeyFilter]) {
+        cacheKeyFilter = context[SDWebImageContextCacheKeyFilter];
     }
+    if (cacheKeyFilter) {
+        key = [cacheKeyFilter cacheKeyForURL:url];
+    } else {
+        key = url.absoluteString;
+    }
+    // Thumbnail Key Appending
+    NSValue *thumbnailSizeValue = context[SDWebImageContextImageThumbnailPixelSize];
+    if (thumbnailSizeValue != nil) {
+        CGSize thumbnailSize = CGSizeZero;
+#if SD_MAC
+        thumbnailSize = thumbnailSizeValue.sizeValue;
+#else
+        thumbnailSize = thumbnailSizeValue.CGSizeValue;
+#endif
+        
+        BOOL preserveAspectRatio = YES;
+        NSNumber *preserveAspectRatioValue = context[SDWebImageContextImagePreserveAspectRatio];
+        if (preserveAspectRatioValue != nil) {
+            preserveAspectRatio = preserveAspectRatioValue.boolValue;
+        }
+        NSString *transformerKey = [NSString stringWithFormat:@"Thumbnail({%f,%f},%d)", thumbnailSize.width, thumbnailSize.height, preserveAspectRatio];
+        key = SDTransformedKeyForKey(key, transformerKey);
+    }
+    
+    return key;
 }
 
 - (SDWebImageCombinedOperation *)loadImageWithURL:(NSURL *)url options:(SDWebImageOptions)options progress:(SDImageLoaderProgressBlock)progressBlock completed:(SDInternalCompletionBlock)completedBlock {
@@ -188,8 +214,7 @@ static id<SDImageLoader> _defaultImageLoader;
     // Check whether we should query cache
     BOOL shouldQueryCache = !SD_OPTIONS_CONTAINS(options, SDWebImageFromLoaderOnly);
     if (shouldQueryCache) {
-        id<SDWebImageCacheKeyFilter> cacheKeyFilter = context[SDWebImageContextCacheKeyFilter];
-        NSString *key = [self cacheKeyForURL:url cacheKeyFilter:cacheKeyFilter];
+        NSString *key = [self cacheKeyForURL:url context:context];
         @weakify(operation);
         operation.cacheOperation = [self.imageCache queryImageForKey:key options:options context:context completion:^(UIImage * _Nullable cachedImage, NSData * _Nullable cachedData, SDImageCacheType cacheType) {
             @strongify(operation);
@@ -303,8 +328,7 @@ static id<SDImageLoader> _defaultImageLoader;
     if (context[SDWebImageContextOriginalStoreCacheType]) {
         originalStoreCacheType = [context[SDWebImageContextOriginalStoreCacheType] integerValue];
     }
-    id<SDWebImageCacheKeyFilter> cacheKeyFilter = context[SDWebImageContextCacheKeyFilter];
-    NSString *key = [self cacheKeyForURL:url cacheKeyFilter:cacheKeyFilter];
+    NSString *key = [self cacheKeyForURL:url context:context];
     id<SDImageTransformer> transformer = context[SDWebImageContextImageTransformer];
     id<SDWebImageCacheSerializer> cacheSerializer = context[SDWebImageContextCacheSerializer];
     
@@ -353,8 +377,7 @@ static id<SDImageLoader> _defaultImageLoader;
     if (context[SDWebImageContextStoreCacheType]) {
         storeCacheType = [context[SDWebImageContextStoreCacheType] integerValue];
     }
-    id<SDWebImageCacheKeyFilter> cacheKeyFilter = context[SDWebImageContextCacheKeyFilter];
-    NSString *key = [self cacheKeyForURL:url cacheKeyFilter:cacheKeyFilter];
+    NSString *key = [self cacheKeyForURL:url context:context];
     id<SDImageTransformer> transformer = context[SDWebImageContextImageTransformer];
     id<SDWebImageCacheSerializer> cacheSerializer = context[SDWebImageContextCacheSerializer];
     BOOL shouldTransformImage = originalImage && (!originalImage.sd_isAnimated || (options & SDWebImageTransformAnimatedImage)) && transformer;