Uploadcare

Uploadcare provides companies with simple, powerful, developer-friendly file uploading, processing & delivery for web apps. With Uploadcare you and your team get a complete out-of-the-box solution, built for engineers by engineers. Uploadcare service include features like webhooks for notifying when your application is about to upload files or trigger actions, document conversion for 12 formats ranging from PDFs to JPEG. Video processing that allow you to crop, trim, adjust resolution, generate thumbnails and encode into MP4, WebM, and OGG. Object recognition that  allow you to tag images with detected objects. Receive a list of objects with certainty values.

Uploadcare provides a free forever plan ($0/month) wich includes 3000 uploads, 30 GB traffic and 3 GB storage.

When the free plan is utilized a Pay as you grow plan kicks in.