CSV Computed Column
Paste or choose a CSV, write an arithmetic formula such as price * quantity, and export the result locally.
A QUICK WALKTHROUGH
How to use this tool
- Choose a CSV file or paste CSV text.
- Enter a new column name and an arithmetic expression using header names.
- Choose blank and non-numeric handling, then download the marked result.
Restricted arithmetic parser
Expressions support header references, decimal numbers, parentheses, unary signs, and +, −, ×, ÷ operators. JavaScript evaluation, calls, properties, and assignments are never used.
Explicit missing-data policy
Choose whether a blank input makes the result blank or marks the row as an error. Non-numeric cells follow their own blank, zero, or error policy, and error rows are visibly marked.
Finite input limits
Processing is local and bounded to a 10 MB file, 100 columns, 50,000 rows, 200-character expression, and 100,000 characters per cell.
GOOD TO KNOW
Common questions
Can formulas run code?
No. Only the documented arithmetic grammar is accepted.
How are headers referenced?
Use the exact header text; headers with spaces or punctuation can be wrapped in backticks.
What happens to bad rows?
The selected policy determines whether they become blank or retain an explicit error marker in the computed cell.