What does the WhatsApp Data Scraper do?

It is a Chrome extension that helps you export and organize contacts, group members, and messages from WhatsApp Web conversations you already have access to. It injects a sidebar into web.whatsapp.com and provides three scrapers with CSV, JSON, and JSONL export.

Does it work on the WhatsApp mobile or desktop app?

No. The extension only works on WhatsApp Web (web.whatsapp.com) in a Chrome or Chromium-based browser. It does not work on the WhatsApp mobile apps or the standalone desktop app.

Does it use the WhatsApp API or send messages?

No. There is no API client, no account connection, and no automation of any kind — no sending, scheduling, auto-replies, or broadcasting. It runs in Web Mode only and reads what WhatsApp Web has already rendered on the page.

Can it reveal hidden phone numbers?

No. Phone numbers appear only if WhatsApp Web already shows them. Hidden numbers are never revealed, and there is no full-history API or deleted-message recovery.

Is my extracted data sent to any server?

No. All extracted data stays in your browser until you export. The only server communication is for account/billing sync and anonymized, PII-free usage analytics. Your WhatsApp content is never sent to Mastros servers.

What export formats are available?

CSV (compatible with Excel and Google Sheets), JSON (pretty-printed array), and JSONL (newline-delimited JSON for streaming pipelines).

How much does it cost?

The Free plan includes 100 profiles/month and 100 messages/month with every scraper unlocked and no account required. Pro adds 5,000 profiles/month and 10,000 messages/month at higher volume. Scale offers 100,000 profiles/month and 500,000 messages/month for high-volume needs.

Is this affiliated with WhatsApp?

No. Mastros is not affiliated with, endorsed by, or partnered with WhatsApp or Meta. Users are solely responsible for complying with WhatsApp's Terms of Service.

Where can I get support?

You can reach us at admin@mastros.online or visit the Support page on this website.

Back to Mastros

WhatsApp Data Scraper

Turn visible WhatsApp Web chats, contacts, and groups into clean, structured exports. Scrape contacts, group members, recent chats, and loaded messages — then download as CSV, JSON, or JSONL. Everything is processed locally in your browser.

Built for backup, research, CRM cleanup, sales and recruiting workflows, community management, and personal record keeping.

Web Mode only · No API · No automation · No signup needed

Get it on the Chrome Web Store

Group Members Scraper

Chat Messages

All Recent Contacts

Three scrapers · CSV / JSON / JSONL

How It Works

Step 1

Install the extension

Add Mastros — WhatsApp Scraper from the Chrome Web Store. Works on any Chromium browser.

Step 2

Open WhatsApp Web

Navigate to web.whatsapp.com and log in. The extension sidebar appears automatically.

Step 3

Choose what to scrape

Pick Group Members, Chat Messages, or Recent Contacts.

Step 4

Export your data

Download as CSV, JSON, or JSONL. Open in Excel, Sheets, or your tools.

Three Scrapers

Each scraper reads only what WhatsApp Web has already rendered, in Web Mode.

Group Members Scraper

Web Mode

Extract every visible member of an open group from the group info list.

Names, phone numbers (when shown), and roles
Reads the rendered group participant list
Counts toward your monthly profile quota
Open a group before you start

Chat Messages

Web Mode

Extract the loaded message history of the open chat, plus its contact card.

Message text, sender, and timestamps
Includes the chat's contact card
Reads only messages already loaded in the chat
No deleted-message recovery — there is no API

All Recent Contacts

Web Mode

Extract names, previews, and numbers from the rows in your chat list.

Name, last-message preview, time, and unread count
Reads the left-hand chat list
Nothing needs to be open
Counts toward your monthly profile quota

Features

Local-first architecture

Scraping happens client-side in your browser. Nothing is uploaded to Mastros servers.

CSV, JSON, JSONL export

Download structured datasets in the format your workflow needs.

No automation, ever

No sending, auto-replies, broadcasting, joining groups, or inviting contacts. It only reads what's already visible.

Saved sessions

Each scrape is saved as a separate session, so you can revisit and re-export your results.

Partial results preserved

If a scrape is stopped or hits your monthly quota, the rows collected so far are kept.

Numbers stay private

Phone numbers appear only if WhatsApp Web already shows them — hidden numbers are never revealed.

Plans

Free

100 profiles/month

100 messages/month

Every scraper unlocked

No account needed

The only limit is monthly volume

Pro

5,000 profiles/month

10,000 messages/month

Everything in Free at higher volume

Best for active operators

Scale

100,000 profiles/month

500,000 messages/month

Everything in Free at the highest volume

Built for high-volume export workflows

Privacy-first by design

Mastros — WhatsApp Scraper does not upload your messages, contacts, phone numbers, chat names, or group names to Mastros servers. Scraping happens client-side in your browser.

Anonymized analytics never include message text, phone numbers, names, chat titles, group titles, or any raw WhatsApp content.

FAQ

Responsible Use

This tool is designed for lawful research, analysis, and community management. Only export data from conversations you have legitimate access to. Comply with WhatsApp's Terms of Service and applicable data protection laws. Do not use exported data for spam, bulk messaging, harassment, or automation. admin@mastros.online

Get the WhatsApp Data Scraper

Free to start, with no signup required. Questions in the meantime? admin@mastros.online

Get it on the Chrome Web Store