Contact person: Mass WhatsApp Number Validator

Phone:Show

Email:Show

Location: Bangalore, India

Budget: Recommended by industry experts

Time to start: As soon as possible

Project description:
"I have millions of phone numbers and I need a Windows-based application that can quickly tell me which of them are registered on WhatsApp and which are not. I will be loading the data through large CSV files, so the import routine has to accept heavy files without crashing or forcing me to split them manually.

Core needs
• Detect “exists” vs “non-exist” status for every number in the CSV and write the results back to a CSV (or similar) with clear flags.
• Process millions of rows in a single run, making full use of available CPU/RAM so the job completes in reasonable time.
• Connection handling that keeps the app stable even if WhatsApp limits or temporary bans appear; automatic retry logic is welcome.
• A clean, no-nonsense GUI: choose CSV, start scan, watch progress, export results.
• User authentication is optional; a simple licence key field or similar toggle is enough if you prefer to include it.

Acceptance criteria
1. Drop-in CSV import of at least 5 million rows without manual splitting.
2. Accurate “exists / non-exist” flagging verified by a 1 000-number test list I will provide.
3. Export matches original input order and preserves all columns plus the new status column.
4. Installer and brief usage guide delivered.

If you have built WhatsApp scrapers, validators, or similar high-volume tools before, let me see a demo or short clip and we can move fast.

We will do a demo with 20k numbers initially & later with 50k to check if the tool is working." (client-provided description)