Instagram does not allow third party applications to post on your behalf. Instagram also does not allow you to post videos from a computer. You'll need to download the video file and transfer it onto a mobile device, then post the video from your phone.
To upload a video to Instagram, you'll first need to get the video on your phone. This can be done with an app such as Dropbox. You will need a Dropbox account and the app on your computer and your phone.
- Sign into your Dropbox account
- Drag and Drop the video file
- Open the Dropbox App on your phone
- Download the video file to your phone
Now you can open Instagram and upload the video.
- Open Instagram App on your phone
- Tap on the Add icon
- Select your video file under Camera Roll
Instagram will default to the 1:1 aspect ratio. To use 16:9 aspect ratio, click the crop button on the left.
- Tap the Crop button to change to 16:9
- Tap Next
- Add a filter if you’d like, and/or mute the video
- Tap the Next
- Add a caption, hashtag, location, or send as a Direct message
- Enable share on Facebook or Twitter if you'd like, and tap Share