Free Online Document Scanners

Feb 06, 2021

How to Scan Online from a Document Scanner

  1. On a desktop, open the online scanning page of Dynamic Web TWAIN in a browser.

    Access Your Scanners From a Browser

  2. You will be prompted to download the Dynamic Web TWAIN package. Install the package after downloading.
  3. Select your scanner from the “Select Source” dropdown.
  4. Click the “Scan” button to interact with scanners.

How to Scan Documents From a Smartphone Camera

  1. On your mobile phone, open the online web capture page from a browser.

    Online Web Capture from Mobile

  2. Click the camera icon in the top left corner to bring up the video stream.
  3. Tap the capture icon to take the snapshot.

Build Your Online Document Scanner Using Dynamic Web TWAIN

The above two document scanning pages are built using Dynamic Web TWAIN. Learn more about the document scanning SDK.

Performance on Large-volume Scanning

Dynamic Web TWAIN SDK enables fast and large-volume scanning. 

All three transfer modes are supported:

  • Native Transfer Mode is used by default. In this mode, images are managed by the service.
  • File Transfer Mode enables images to be transferred directly to the hard disk. If the scanner compresses the scanned images fast enough and the hard disk has a high write speed, then the pages can be scanned at the top speed of the scanner.
  • Memory Transfer Mode is also supported and may help in cases where the client machines have limited physical memory.

With disk caching, theoretically, there is no limit on how many pages can be scanned.

All extra information about the images can be obtained so long as the information is transmitted via TWAIN APIs.


  • APIs which take time can be called asynchronously.
  • An image processing SDK can use a lot of memory. However, our SDK has an API to cap memory usage. When the limit is reached, disk caching is enabled.
  • 64-bit service is available to handle large data with high performance.
  • The enhanced mode supports multiple concurrent users in environments like Citrix.

Upload as Images and PDF

  • Speed: The upload module can utilize multiple threads.
  • Compression: Multiple compression algorithms are available. Specifically, JPEG encoding for TIFF and JPEG2000 and JBIG2 for PDF are in place to reduce the size of the compressed files.


Software security is always a great concern. Dynamsoft has built-in many basic and advanced security features to give you peace of mind.

Here are basic security features:

  • Built-in HTTPS support with a configurable SSL certificate.
  • Digital signatures are applied to all binary files of the SDK.
  • Various authentication support for data downloading/uploading, e.g., Basic/Windows/Forms authentications, etc.
  • MSIs provided for massive end-user distribution via Group Policy.
  • The non-admin installer provided for installation without admin rights.
  • Completely independent deployment. No external connections are needed when using the SDK.
  • Configurable authorizations for accessing local resources (files, scanners, webcams).
  • By default, only requests sent from localhost are processed. This can prevent illegal usage of the SDK.