File size limits by format
FileMira processes files locally in your browser. Limits vary by format because different file structures use different amounts of browser memory.
The largest file Free can open is a 10.0 MB Log. The largest Pro can open is a 30.0 MB Log. Every other format is lower — the table below is the whole answer.
| Format | Category | Free | Pro |
|---|---|---|---|
| Markdown | Text & code | 2.0 MB | 15.0 MB |
| SQL | Text & code | 2.0 MB | 15.0 MB |
| TXT | Text & code | 2.0 MB | 15.0 MB |
| HTML | Structured data | 2.0 MB | 10.0 MB |
| JSON | Structured data | 2.0 MB | 10.0 MB |
| XML | Structured data | 2.0 MB | 10.0 MB |
| YAML | Structured data | 2.0 MB | 10.0 MB |
| TOML | Structured data | 512.0 KB | 1.0 MB |
| SVG | Vector graphics | 2.0 MB | 8.0 MB |
| CSV | Tabular data | 5.0 MB | 25.0 MB |
| Log | Line-based data | 10.0 MB | 30.0 MB |
| JSONL | Line-based data | 3.0 MB | 25.0 MB |
| XLSX(compressed) | Spreadsheet | 1.0 MB | 15.0 MB |
| DOCX(compressed) | Document | 1.0 MB | 15.0 MB |
Important notes
- Compressed formats are checked twice. XLSX and DOCX are ZIP packages. The size in the table is the file on disk; after unpacking, the contents are checked against a second cap of 10.0 MB on Free and 500.0 MB on Pro. Office documents typically compress at about 9:1, so an ordinary file under the first cap clears the second.
- Structure has limits too. An Office file can sit under the size cap and still be refused as unusually complex:Worksheets per workbook50 Free · 100 ProRows per worksheet50,000 Free · 200,000 ProCells per workbook500,000 Free · 2,000,000 ProParagraphs per document50,000 Free · 100,000 ProEmbedded images200 Free · 500 Pro
- On a phone or tablet, the Free column applies to everyone.A subscription does not raise the limit there, because what constrains it is the device's memory rather than the plan. The Pro column is what a desktop browser gets.
- Browser-local:Your files stay in your browser. No upload, no server processing. The caps exist because your browser's memory is the machine doing the work.
Frequently asked questions
Why are JSON limits lower than CSV?
JSON usually needs a complete nested structure in memory, while CSV can be processed progressively by rows.
Why are the XLSX and DOCX limits so much lower than the rest?
Because the number that matters is the unpacked size, not the packed one. A 1.0 MB Word file expands to roughly the 10.0 MB the Free cap allows. Publishing the compressed figure is what keeps the refusal at the moment you choose the file, instead of partway through opening it.
Is Pro unlimited?
No. Pro provides larger tested limits while keeping hard safety caps to protect browser stability. The Pro column above is the whole of it.
Can I open a file larger than the limit?
To protect browser stability, FileMira cannot process files above the maximum safe limit. Try splitting the file into smaller parts.
Need larger limits?
FileMira Pro raises every row in the table — up to 15.0 MB for Office files and 30.0 MB for logs.
View FileMira Pro