If you can control both IFRAME content and parent window then you need the Iframe-Resizer.
This library enables the automatic resizing of the height and width of both same and cross domain iFrames to fit their contained content. It provides a range of features to address the most common issues with using iFrames, these include:
- Height and width resizing of the iFrame to content size.
- Works with multiple and nested iFrames.
- Domain authentication for cross domain iFrames.
- Provides a range of page size calculation methods to support complex CSS layouts.
- Detects changes to the DOM that can cause the page to resize using MutationObserver.
- Detects events that can cause the page to resize (Window Resize, CSS Animation and Transition, Orientation Change and Mouse events).
- Simplified messaging between iFrame and host page via postMessage.
- Fixes in page links in iFrame and supports links between the iFrame and parent page.
- Provides custom sizing and scrolling methods.
- Exposes parent position and viewport size to the iFrame.
- Works with ViewerJS to support PDF and ODF documents.