M365 Copilot breaks the 1.5 million word barrier
Microsoft has announced a major upgrade for M365 Copilot: the processing capacity is being increased to up to 1.5 million words per file — equivalent to about 3,000 pages of text. This marks a significant advancement, as it surpasses the previous limit of 300,000 words (around 600–800 pages) by a wide margin.
Added value: Productivity 
Scenario: Data Processing 
Reading time: 5 minutes 
Difficulty: Beginner
Evaluation of the function
How does the function perform?
The expansion is still rolling out
This feature has not yet been activated in our tenant. When asked, Copilot confirms that it can currently handle files of up to approximately 300,000 words (about 600–800 pages) reliably, while the upgrade to 1.5 million words is still under development.
Evaluation and context
The increased processing capacity marks a major leap forward for working with large-scale documents. While the previous limit was sufficient for everyday use, this new capability opens the door to complex analyses and the processing of extensive materials.
Advantages:
- Process very large documents in a single run
- Less manual effort splitting files into smaller parts
- Broader contextual understanding during analysis
Disadvantages and Challenges:
- Processing extremely large files remains technically demanding
- The middle sections of long texts may still only be sampled
- Higher resource consumption and potentially longer processing times
- Possible inaccuracies when summarizing extremely long content
- Output quality strongly depends on file structure
Scenarios
Analyze comprehensive research reports
Researchers and academic departments can now analyze full dissertations, studies, or reports in one go. Instead of extracting and processing chapters individually, Copilot can capture the entire context to produce more accurate summaries and insights.
Consolidate extensive project documentation
Large projects often generate hundreds of pages of documentation. With the increased capacity, project managers can have all materials analyzed together — identifying cross-references, inconsistencies, or progress gaps — saving significant time compared to manual review.
Review legal documents and contracts
Legal professionals can now process complete contracts, statutes, or case law in full. This enables a deeper examination of risks, contradictions, and hidden clauses — reducing the time spent on manual document review.
Tips for working with large documents
Even with expanded capacity, working with very large documents still poses challenges. Copilot recommends:
- Use structured content: Documents with headings, sections, and a table of contents enable more targeted analysis. Unstructured text makes processing much harder.
- Ask focused questions: Instead of requesting a full summary, ask specific questions about sections or themes. This yields more precise answers.
- Mind prioritization: In long documents, introductions and conclusions are often analyzed more thoroughly than middle sections. Place key information accordingly.
- Process in sections: Uploading large documents in smaller parts can result in more accurate insights — a useful alternative if full-document analysis doesn’t meet expectations.
Special considerations and practical limitations
Despite the impressive upgrade, there are still practical factors to keep in mind:
- Format dependence: Complex formatting, embedded objects, or tables can reduce effective capacity.
- Storage and load times: Very large documents require more disk space and take longer to process.
- Platform differences: Availability and implementation may vary by platform (Web, Windows, Mac).
- License dependency: Some features are limited to Enterprise Copilot licenses.
Conclusion
The expanded processing capacity is an important step toward making Copilot more powerful for professional use cases involving large documents. It addresses a key limitation and unlocks new opportunities in document analysis and generation — strengthening Copilot’s position as a true productivity accelerator.