Lead databases
CPA, CPL & RSH on databases: partnering with a lead supplier
Payment models for lists and leads: CPA, CPL, RSH. Terms and Telegram @BasesAff on Checkfast.pro.
2026-08-10 · 4 min
Checkfast.pro
Blog
OSINT, security and counterparty checks
92 articles · 16 categories
API & automation
Checkfast.pro Reseller API: integrate bulk checks in 30 minutes
REST API: balance, checkers, check, tasks, download. Phone intelligence for CRM, antifraud, SaaS. Bearer token, USDT billing.
2026-08-09 · 4 min
Compliance
GDPR and phone lists: compliance for bulk number checks
Personal data, consent, controller vs processor, retention. Bulk WhatsApp/Telegram checks on Checkfast.pro.
2026-08-07 · 4 min
Data quality
E.164 phone normalization before bulk WhatsApp & Telegram checks
International +country format, Excel pitfalls, false negatives in ws/tg. TXT/CSV prep guide for Cheker.pro.
2026-08-05 · 4 min
Strategy
Checker waterfall: phonecheck → active → messenger → SMS
Combine task types for lowest cost per delivered message. Phone intelligence pipeline on Cheker.pro.
2026-08-03 · 4 min
Messenger & social checks
How to bulk-check Telegram numbers — tg on Checkfast.pro
Telegram Checker (tg): Basic Telegram number verification. Bulk Telegram checks from 1,000 lines, CSV export & Reseller API on Checkfast.pro.
2026-08-02 · 4 min
Messenger & social checks
How to bulk-check Telegram numbers — tg_active on Checkfast.pro
Telegram Days Checker (tg_active): Telegram account activity days detection. Bulk Telegram checks from 1,000 lines, CSV export & Reseller API on Checkfast.pro.
2026-07-31 · 4 min
Messenger & social checks
Telegram checker tg_avatar: use cases, compliance & integration
Telegram Age & Gender Checker (tg_avatar): Comprehensive Telegram profile analysis including age, gender, avatar and activity data. Bulk Telegram checks fr…
2026-07-29 · 4 min
Messenger & social checks
How to bulk-check WhatsApp numbers — ws on Checkfast.pro
WhatsApp Real-time Checker (ws): Service based on fully real-time detection. Bulk WhatsApp checks from 500 lines, CSV export & Reseller API on Checkfast.pro.
2026-07-27 · 4 min
Messenger & social checks
How to bulk-check WhatsApp numbers — ws_active on Checkfast.pro
WhatsApp Days Checker (ws_active): Detect WhatsApp account activity duration, whether it is a business account, and signature information. Bulk WhatsApp ch…
2026-07-25 · 4 min
Messenger & social checks
WhatsApp checker ws_avatar: use cases, compliance & integration
WhatsApp Age & Gender Checker (ws_avatar): Comprehensive WhatsApp data analysis. Bulk WhatsApp checks from 500 lines, CSV export & Reseller API on Checkfast.pro.
2026-07-23 · 4 min
Messenger & social checks
How to bulk-check Number Checker numbers — phonecheck on Checkfast.pro
Phone Number Validation (phonecheck): Validate numbering format, line type, and reachability signals before running platform-specific checks. Bulk Number C…
2026-07-21 · 4 min