After you upload image to your post, and choose to display it as original, your image URL will be like below:
The text /s1600/ in the URL will tell with Blogger / Blogspot image hosting that you want the original size version of the image.
** NOTICE: However, in some special cases, Blogger will only show a small version at s1600 for very long / big images (example: infographic images). In that case, you must increase the size to equal your image height to access the real original version, example: s5000 if your image height is 5000 pixels.
Specific Max Width
If you want to load image which is NOT LARGER than 200px in width (height is auto), you will replace s1600 to w200 like below:
If the width you set in the URL is larger than the original width, Blogger / Blogspot image hosting will return the original size version. That’s why we call it “Max Width”.
Specific Max Height
Specific Max Width and Max Height
The return version will have width no larger than 200px and height no larger than 30px and also keeping scale ratio of original version.
If you want to load image with EXACTLY width and height, example 300px in width and 100px in height, you must replace s1600 to w300-h100-c. The -c text at the end is “crop”. The final URL will be:
If you want to crop image as SQUARE, example, loading size 300px in both width and height, you can replace s1600 to s300-c:
If you want to provide a download link for image, you can add -d at the end of size:
If you want to provide a XML object for image, you can add -g at the end of size:
Hope those tips will help you optimizing your thumbnails better for your templates.