CSV to Parquet
Convert CSV files to Parquet format
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Accepted formats: .csv • Max size: 25MB
About CSV to Parquet Converter
1What is it?
Convert CSV files to Parquet format for massive compression and faster analytics. Achieve 70-90% file size reduction while enabling lightning-fast queries. This tool automatically infers column types (numbers, dates, booleans) from your CSV data and generates optimized Parquet files using Apache Arrow and parquet-wasm. Perfect for data engineers preparing data for Spark, Athena, or BigQuery.
2Use Cases
- Compress large CSV files for efficient storage (70-90% smaller)
- Prepare CSV data for upload to data lakes (S3 + Athena, BigQuery)
- Convert CSV exports to Parquet for faster Spark processing
- Optimize CSV files for analytics and data warehousing
3Examples
Compression
Input
sales_data.csv (50MB)
Output
sales_data.parquet (7MB) - 86% smaller
Log Optimization
Input
logs.csv (200MB)
Output
logs.parquet (25MB) - 87% reduction
?Frequently Asked Questions
How does Parquet achieve such high compression?
Parquet uses columnar storage (stores columns together, not rows) combined with efficient encoding schemes. Similar values compress extremely well - for example, a column with many repeated values or a numeric column with a small range compresses to a tiny fraction of its CSV size.
Does it automatically detect column types?
Yes! The converter analyzes your CSV data and infers types: integers, floats, dates, booleans, and strings. This ensures optimal compression and query performance. You can review the detected schema before downloading.
Can I use the Parquet file with AWS Athena or BigQuery?
Absolutely! The generated Parquet files follow the Apache Parquet specification and work perfectly with AWS Athena, Google BigQuery, Snowflake, Apache Spark, and any other tool that supports Parquet.