Knowledge hub
Short, practical guides to buying, checking and working with country contact datasets.
Basics
What is a business contact database?
What a business contact dataset contains, what it does not contain, and how buyers typically use one lawfully.
What is B2C contact data? Individual phone and email lists explained
What a B2C (consumer) contact dataset contains, how it differs from B2B business data, and what you must check before using individual phone or email lists.
Buying data
How to buy a phone number list by country (2026 buyer's guide)
What to check before you buy a phone number list or mobile number database: record counts, phone coverage, format, freshness, repeat orders and the rules for calling.
How to choose telemarketing lists and cold calling data
A practical checklist for call centres and sales teams buying telemarketing data: volume planning, dialer-ready formats, duplicates between orders, and do-not-call screening.
Data quality
How duplicate records are measured and removed
The difference between exact duplicates, near duplicates and repeat purchases — and which of these figures we measure automatically.
How to normalise international phone numbers
Convert phone numbers to E.164 format so they match across files, dial correctly and de-duplicate reliably.
How to evaluate data freshness
What 'last processed' means, why no seller can guarantee every record is current, and what evidence to look for.
How to measure contact database quality
A practical checklist of quality measures — coverage, validity, uniqueness and consistency — and how to compute them yourself.
How to measure email coverage in a contact dataset
Email coverage is the share of records with a usable email address. How to measure it yourself, what counts as a valid email, and how to read the coverage figures on a dataset page.
How to inspect a contact-data sample before you buy
A short checklist for reading a dataset's structure preview, data dictionary and sample file: columns, coverage, formats, duplicates and source flags.
How it works
How to pay with crypto (blockchain payment guide)
Step-by-step: choose an asset and network, send the exact amount, paste your transaction hash (TXID), and DataPackHub verifies the payment directly on the blockchain.
How our 50K SmartPacks work
Every dataset is split into numbered files of about 50,000 records. Your account remembers which packs you have, so repeat purchases never include the same pack twice.
How data pack versioning works
Datasets are released as versions such as UK-BIZ-2026-09. Delivered packs are recorded with their version and checksum so every purchase stays traceable.
Working with files
CSV vs XLSX for contact datasets
When to download CSV and when to download XLSX, with the practical limits of each format.
How to import large CSV files
Practical steps for opening or importing CSV files with hundreds of thousands of rows without crashes or corrupted phone numbers.
How to merge multiple CSV files
Combine several packs into one file safely: matching headers, keeping encodings consistent and removing duplicates afterwards.