---
title: "Document import specification"
slug: "document-import-specification"
updated: 2025-10-24T10:02:43Z
published: 2025-10-24T10:02:43Z
canonical: "knowledge-base.rossum.ai/document-import-specification"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://knowledge-base.rossum.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Document import specification

Documents may be imported into Rossum using the **REST API** or **email gateway**. To ensure successful import and subsequent processing of documents in Rossum, files must meet certain criteria. We divide them to **requirements** (these must be matched for a file to be processed by Rossum) and **recommendations** (following which guarantees the highest possible processing reliability).

Rossum **extracts data from all document pages**. This behavior can be limited to extraction only from several initial pages. It is generally not necessary to remove additional pages of other types (for example a purchase order appended after an invoice). **Splitting of documents** can be done **manually via UI**or automatically using a special [**Separator page**](https://elis.rossum.ai/api/docs/#export).

## File Requirements

- **Import channels**
  - You can import documents via the web app (manual upload), REST API, or email.
- **Supported file formats**
  - PDF, PNG, JPEG, TIFF, XLSX/XLS, DOCX/DOC. (Rossum also accepts .zip archives as a container; see ZIP rules below.)
- **File size limits**
  - Max 40 MB per file.
  - For .zip uploads, the uncompressed total of all contained files must not exceed 40 MB.
- **ZIP archives**
  - Fewer than 1000 files per archive.
  - Only files in the root of the archive are processed (or files inside a single first-level directory if that’s the only item).
  - The same ZIP rules apply to uploads via API, email, and web app.
- **Email import limits**
  - Email size limit: 50 MB (raw email, including base64-encoded attachments).
  - Rossum extracts PDFs, images, and ZIP files from incoming emails.

## Document Specification

- Image resolution should be **at least 150 DPI** in case of scans/photos
- Minimum font size on a document should be 6pt
- Documents should be in **A4 or Letter format** (small-size documents like receipts should be scanned on top of a blank A4 page)
- One page may contain only one document (i.e. two receipts on one page cannot be extracted separately)
- Scans should not have extremely large dimensions, ideally **no more than 3000 pixels on each side**
- Maximum **50,000 extracted fields of all types per document is supported**; in case of master data enum fields, every two enum rows count as an additional field