SmartQueryTools

Rename Columns in Parquet Files Online

Rename columns in Parquet files instantly in your browser. No upload, no server — your data stays on your device.

How to rename Columns in Parquet files

  1. Drop your file onto the upload area. Every column is listed with its current name on the left and an editable box on the right.
  2. Type a new name into the box for each column you want to change. Edited boxes are highlighted. Leave the others as they are.
  3. Click Apply Renames. The button stays disabled until at least one name differs from the original.
  4. Check the preview, then click Download to save the file with the new headers in the same format.

Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.

Worked example

A customer survey tool exports question text as column headers. The analyst wants short snake_case names before loading the results into a database.

Input (Parquet)

Parquet file (binary, columnar) — shown as a table with its schema

Respondent IDQ1: How satisfied are you?Q2: Would you recommend us?Submitted At
14true2026-06-02
22false2026-06-02
35true2026-06-03

Schema: Respondent ID BIGINT, Q1: How satisfied are you? BIGINT, Q2: Would you recommend us? BOOLEAN, Submitted At DATE

Settings

  • Respondent ID → respondent_id
  • Q1: How satisfied are you? → satisfaction
  • Q2: Would you recommend us? → would_recommend
  • Submitted At → submitted_at

Result

respondent_idsatisfactionwould_recommendsubmitted_at
14true2026-06-02
22false2026-06-02
35true2026-06-03

Only the headers change. Every value, the row order and the column order stay exactly as they were, and each column keeps its type: the scores remain integers and the recommend answers remain booleans. Names without spaces or punctuation can be used in SQL without quoting.

Working with Parquet files

Parquet stores column names in the file schema, so a rename rewrites the whole file with the new schema. Types, nullability, decimal precision and nested struct fields are kept as they were. Only the top-level names change. Field names inside a struct cannot be edited here. Because the file is rewritten, row groups and compression are regenerated, but the values are identical. A struct column is listed like any other and can be renamed as a whole. Nullability and field order in the schema stay as they were.

Parquet itself accepts almost any UTF-8 name, but the systems that read it are stricter. BigQuery column names allow only letters, digits and underscores. Older Spark and Hive versions reject spaces and characters such as commas, semicolons, braces and equals signs. Renaming to snake_case before loading avoids those errors. Column names are case-sensitive in the file, so Amount and amount count as different names to readers that respect case.

Frequently Asked Questions

Why does Spark or BigQuery reject my Parquet column names?

Those systems restrict characters in column names. Spaces, commas, semicolons, braces and parentheses are common problems. Rename them to letters, digits and underscores here, then load the file again.

Does renaming Parquet columns change their types?

No. Each column keeps its type. Only the name in the schema is replaced.

What happens if I give two columns the same name?

Column names must be unique, so the engine adds a numeric suffix to the repeated name, for example total and total_1. Check the preview before downloading.

What if I clear a name box completely?

An empty box is ignored and that column keeps its original name. Leading and trailing spaces in a typed name are also removed.

Does renaming change any data?

No. Only the headers change. Values, types and the order of rows and columns stay the same.

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