Why format Excel online
Raw exports look plain: weak headers, messy dates, cramped columns, and phone numbers you cannot send externally. ComTools Excel Format (Tools/Excel/Format) uploads a table, configures styles, previews, and downloads a polished .xlsx.
Supported input
| Format | Notes |
|---|---|
.xlsx, .xlsm, .xltx, .xltm |
Workbook (first sheet) |
.csv |
Comma-separated |
.json |
Object array or 2D array |
.html, .htm |
HTML table snippet |
Pair with HTML to Excel or upload html directly here.
Options
Theme presets
Classic blue / green / gray / purple / red—one-click header colors.
Data formats
- Date:
yyyy-MM-dd,dd/MM/yyyy, custom pattern - DateTime: including
yyyy-MM-dd HH:mm:ss, ISOTform - Decimal: integer, 2 decimals, thousands, percent, scientific, custom
Header row
- Freeze top row, auto-filter
- Bold, font size, font and fill colors
Body
- Zebra alternate row shading
- Column width: auto / max cap
- Row height: auto / max cap
Advanced
- Hyperlinks for URLs and emails
- Data masking for email/phone columns on export (preview unmasked)
Steps
- Open Excel Format.
- Upload Excel, CSV, JSON, or HTML.
- Adjust format settings and theme.
- Review preview (first ~10 data rows).
- Export the formatted
.xlsx.
Common scenarios
| Scenario | Settings |
|---|---|
| Client report | Classic blue + zebra + freeze/filter |
| Unify dates | yyyy-MM-dd |
| External share with PII | Enable masking |
| From web table | HTML to Excel → this tool |
| Then dedup / SQL | Dedup → INSERT |
Notes
- First worksheet only—split multi-sheet files first.
- Preview is partial; export includes all rows.
- Masking uses header names (email/phone) and content heuristics.
- Server-side processing—mind sensitive data.
Related tools
| Need | Tool |
|---|---|
| Styling only | This guide |
| Web table capture | HTML to Excel |
| CSV for systems | Excel to CSV |
| Before/after diff | Excel Compare |
FAQ
JSON shape?
Prefer [{"id":1,"name":"a"}]—keys become headers.
CSV garbled?
Use UTF-8 or CSV to Excel first.
Keep formulas?
Formatting rewrites styled values—backup formula-heavy sheets first.
vs Excel Table Styles?
No install; JSON/HTML input, masking, and uniform date/number rules for pipelines.