CSV Group & Aggregate — Count, Sum, and Average by Key Columns

2025.11.12
Load CSV

Or paste:

Delimiter:
Grouping keys
Key normalization:
Aggregations
Sum columns (optional, comma-separated): * Non-numeric cells are ignored. Commas and % are stripped.
Average columns (optional, comma-separated): * Averages use only cells that are valid numbers as the denominator.
Output Output delimiter:

How to use (3 quick steps)

  1. Load your CSV
  • Upload a file or paste CSV text.
  • Choose the delimiter (Comma / Tab / Semicolon / Pipe).
  • Check “First row is header” if your file has headers.
  1. Set grouping & measures
  • In “Key columns,” specify one or more columns by 1-based index (e.g., 1,3) or by header names (e.g., Department,Date).
  • Optionally specify columns to Sum and/or Average (by index or header).
  • You can normalize keys: trim spaces, collapse repeated spaces, and match case-insensitively.
  1. Run & download
  • Click “Aggregate” to preview (up to ~200 rows).
  • Download the full result as a UTF-8 CSV.

What you get (output)

  • A new CSV grouped by your key columns.
  • Optional “count” column (rows per group).
  • Sum columns with suffix “__sum” (non-numeric cells ignored; commas and % removed).
  • Average columns with suffix “__avg” (denominator counts only numeric cells).
  • Header row included if selected; delimiter matches your choice (Comma / Tab / Semicolon / Pipe).
  • UTF-8 output, suitable for spreadsheets and databases.

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Notes & caveats

  • Key columns: numeric indexes are 1-based from the left (1,2,3…). Header names must match exactly (after optional normalization for comparison).
  • Normalization scope: trimming, case-folding, and whitespace-collapse apply only to key comparison; source cell values are not modified.
  • Irregular rows: shorter rows are padded with blanks so the table remains rectangular.
  • Encoding: loader auto-detects UTF-8 / SJIS-win (CP932) / EUC-JP / JIS and converts to UTF-8. If characters look wrong, recheck delimiter and source encoding.
  • Excel tip: import via “Data → From Text/CSV” and select UTF-8 to avoid mojibake.
  • Limits & access: default file size limit 5 MB (change with max_mb). By default login is required; set require_login=0 to make it public.
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