Tvarka Sign and electronic signatures

Uploading documents safely: size limits, SHA-256 and container checks

The Tvarka Sign upload path checks the file type, the size, duplicates, and the state of signed containers.

Updated: 2026-08-20 Query: upload documents safely SHA-256 hash ADOC ASiC-E 50 MB limit

What to know before uploading

Tvarka Sign accepts the common working formats: PDF, Office and text documents, images, and ADOC and ASiC-E containers. The maximum size of a single file is 50 MB.

A SHA-256 checksum can be used during upload. It lets the server confirm that what arrived is the same file the browser or the desktop application sent.

Why containers are checked separately

ADOC and ASiC-E are not plain files. Inside there can be several documents, signatures, metadata and timestamps. So Tvarka checks them, shows what is inside, and establishes whether the document can still be signed.

For PDF documents Tvarka also checks whether the file already carries electronic signatures.

Frequently asked questions

What is the size limit for one file?

The public Tvarka Sign guides and tools state a 50 MB limit for a single file.

What is a SHA-256 checksum?

It is a digest of the file that helps confirm the file did not change in transit.

Can I upload ADOC and ASiC-E?

Yes. Tvarka reads them as containers and shows their contents and signature information.

Sources