Browser Tool
Free CSV Validator
Clean your data before you import. Validate emails, phone numbers, and check for duplicates instantly.100% Client-Side. Your data never leaves your browser.
Upload your CSV file
Drag and drop or click to browse
Why validate?
Stop bad data at the door.
Implementation projects often stall because of messy client files. A quick pre-check saves hours of debugging import errors later.
- Instant feedback on file quality
- Remove invalid rows in one click
- Secure - no data upload to server
- Share clean files with your team
Need complex logic?
This validator handles simple checks perfectly. For conditional logic, cross-reference lookups, and AI-assisted mapping, teams use DataFlowMapper to automate complex transformations.
Explore DataFlowMapperClient-Side Processing ArchitectureSecure
Your data never leaves your device. All processing happens locally in your browser's memory via WebAssembly/JavaScript. This ensures complete data sovereignty and compliance with GDPR, HIPAA, and SOC2 standards as no files are uploaded to our servers.
Frequently Asked Questions
Is my data safe/private?▼
Yes. This tool runs 100% in your browser. Your file data is processed locally in your device's memory and is never uploaded to our servers or seen by us.
How do I validate a CSV file?▼
Simply upload your file, and use the dropdowns above each column to select validation rules (e.g., Email, Phone, Unique). The tool instantly highlights errors for you to review.
Can I remove duplicates?▼
Yes. Select the 'Unique' rule for your identifier column. The tool will flag duplicate entries, and you can download a clean version with duplicates removed.
Is there a file size limit?▼
Because processing happens on your device, the limit depends on your computer's RAM. Most modern laptops can handle files up to 100MB-500MB without issues.
The visual data transformation platform that lets implementation teams deliver faster, without writing code.
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