Process 5 Million Rows.
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Natively GDPR compliant. Safely clean PII and financial datasets without legal risks.
Processing a 1 GB CSV file
Excel
❌
Crashes / OOM
ChatGPT
❌
File too large
dataprep.dev
✅
~0.8s
Toolkit Highlights
CSV Merger
Drag in 50 CSV files with mismatched columns and merge them into one unified table.
Open toolJSON ↔ CSV Converter
Flatten deeply nested JSON arrays into a clean CSV with dot-notation column names.
Open toolShopify Order Normalizer
Collapse Shopify's multi-line order export into one row per order with aggregated totals.
Open toolLocal VLOOKUP (Joiner)
Join two large CSV files on a shared key column instantly without Excel freezing.
Open toolReal-world Cleaning SOPs
How to Merge 50 Shopify Order CSVs Into One File Without Crashing Excel
Shopify caps order exports at ~10,000 rows. Paste a few months of high-volume store data into Excel, cross 150K rows, and watch it freeze ('Not Responding'). This workflow merges dozens of fragmented CSVs, deduplicates by Order ID, and realigns shifted columns (like missing Billing Country in older exports). The output is a clean, flat table ready for Triple Whale ingestion, Pivot Tables, or LTV/ROAS analysis.
Read workflowHow to Anonymize Customer Data Before Sharing with ChatGPT or Claude
Your raw customer CSV contains toxic PII. Pasting it into ChatGPT sends that data to OpenAI's servers—risking a Samsung-style corporate leak. This SOP local-masks names, emails, phones, and IPs using browser-based hashing. It preserves column types and statistical structures for LLM analysis, rendering the output completely untraceable to real users.
Read workflowHow to Clean Apollo Exported Leads Before Importing into Cold Email Software
Apollo exports include 'guessed' emails and hidden spam traps. Importing raw Apollo CSVs into Instantly guarantees an automatic campaign pause. This 4-step workflow filters out non-verified addresses, purges role-based targets (info@, admin@), flags catch-all domains, and formats the header row for zero-mapping imports into Smartlead or Lemlist.
Read workflowTest with Dummy Data
Shopify Order Export Sample CSV (Dirty + Clean)
A production-realistic Shopify order export (200 rows) covering the exact scenarios that break data pipelines: multi-line items (one order → multiple rows), partial refunds, mixed fulfillment statuses, and discount code stacking. Download both a 'dirty' raw export (containing trailing spaces and HTML entities) and a 'clean' normalized version. Perfect for testing ShipStation ERP imports, QuickBooks reconciliation, or Shopify API mock data. All data processing happens locally in your browser — your order data never leaves your machine.
View datasetAmazon FBA Settlement Report Sample Data
A representative Amazon Seller Central settlement report (TSV format) with 150 transactions. It covers all critical row types: Orders, Refunds, FBA Fees, Adjustments, and Transfers. The 'dirty' version includes common beginner traps like Transfer rows (which cause double-counting) and TSV delimiter issues that break Excel. The 'clean' version shows a collapsed profit summary ready for QuickBooks import. Ideal for auditing FBA fees or testing automated profit calculation scripts without exposing your actual store revenue. All processing runs locally — your financial data never touches a server.
View dataset