Calculate each row's share of the column total as a percentage
Add a percentage-of-total column showing each row's share of the column sum.
🛡️ Your rows never leave your browser.
Why Onfyt: Supports group-level denominator—e.g., each product's share of its category subtotal rather than the grand total.
Interactive Sample Data
| region | revenue |
|---|---|
| Nairobi | 4500 |
| Mombasa | 3200 |
| Kisumu | 1800 |
How this tool works
Knowing each category's share of the total is a fundamental analytics question: what percentage of total revenue comes from Nairobi? From Solar products? This tool adds a pct_of_total column (revenue / SUM(revenue) × 100) to your CSV.
Group-level percent-of-subtotal: optionally compute each row as a percentage of its group's subtotal rather than the grand total.
Computing each row's proportional contribution relative to the aggregate column sum reveals concentration ratios and portfolio breakdowns for financial auditing.
Computing each row's percentage contribution relative to the column total reveals concentration ratios, market share breakdowns, and portfolio asset allocation. Our engine calculates exact percentages with customizable decimal formatting.
Proportional percentage calculations compute each row's share of the global total or category subtotal, automatically handling zero-sum denominators and presenting clean, formatted distribution ratios for executive summaries. Fractional contribution metrics provide immediate visibility into concentration risks, highlighting key revenue drivers and major cost centers across departments. Proportional distribution metrics empower analysts to detect revenue concentration issues and operational volume imbalances across business units with complete clarity across all reporting tiers and organizational performance dashboards.
Computing each observation's fractional share of the overall total highlights revenue concentration and major expenditure drivers. Clear proportional breakdowns reveal portfolio distribution metrics directly. Automatic precision formatting formats computed proportions with customizable decimal places and optional trailing percentage glyphs for direct presentation. Dynamic denominator recalculation updates proportions automatically if upstream rows are filtered or modified. Proportional distribution metrics reveal key revenue drivers and major cost centers across departments clearly.
Things that usually go wrong
- If the column sum is zero, division produces NaN — the tool outputs 0% for all rows.
- Non-numeric values contribute 0 to the sum.
Edge cases we tested
🧪 Column total is 0
Division by zero handled; pct_of_total set to blank with a warning.
🧪 Column sum equaling zero
Guards against division-by-zero errors returning 0%.
Frequently Asked Questions
Are percentages rounded?
To 2 decimal places. The sum of all percentages may be 99.99% or 100.01% due to rounding.
Can I compute percent of a grouped total?
Group By first, then run Percent of Total on the count/sum column.
Related tools
Analyze
Count Word Frequency
Count word frequency across a text column in a CSV and output a frequency table.
Open Tool →
Analyze
Count Unique Values
Count distinct values per CSV column and generate a value-count frequency table for each.
Open Tool →
Analyze
Top N Values in a Column
Extract the top N or bottom N rows from a CSV ranked by a numeric column.
Open Tool →