Paperless-ngx is itself a free, open-source, self-hosted document management system with OCR and machine-learning-based tagging — it's not proprietary, so people looking for an "alternative" here are usually after a different feature set or workflow, such as lighter-weight archiving with simpler ingestion.
Papra is another open-source option worth comparing if you want something more minimalistic, focused on search, tags, and email ingestion rather than Paperless-ngx's full OCR and auto-classification pipeline.
FAQ
Is there a free, open-source alternative to Paperless-ngx?
Yes. Papra is open source (AGPL-3.0) and free to self-host.
What's the best open-source alternative to Paperless-ngx?
Papra is a lighter-weight option if you mainly need archiving, tagging, and email ingestion, rather than Paperless-ngx's heavier OCR and machine-learning classification pipeline.
What are the top open-source alternatives to Paperless-ngx?
Browse all open-source alternatives to Paperless-ngx above, or explore the full Document Management category for more options.