Well they are advertised as 11 12 inches long it inside measures only at top 9 12 inches and inside bottom only 9 inches... width is advertised as 8 inches wide which it is but inside only measures 6 12 at top and 6 inches at bottom.  Wish they would give inside dimensions.  My envelopes are 5x 712 inches so thought 8 inches was great.  Not so! I will use them to reorganize my pantry...otherwise they are sturdy.