
Mailflow.sh
Stackmail is a webmail service whereby you can log in to your emails from any browser at any time!

Postio.co.uk
Ideal postcodes
Fetchify
Smarty
Data8 UK
ZIP Code API
Data8 UK PredictiveAddress
The most affordable postal code API. 240+ countries, sub-5 ms responses. Simple, elegant, transparent.
Which is more popular?
Website, pricing, platforms and company facts side by side.
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|---|---|---|
| Website | stackmail.com | postaldatapi.com |
| Pricing | — | |
| Company | — | Startup from the United States · 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


No description of StackMail yet.
PostalDataPI is a global postal code validation and enrichment API covering 240+ countries and territories. One API, one key, one flat rate — $0.000028 per query with no tiers or subscriptions. What you get back: Up to 18 metadata fields per postal code — city, state/region, coordinates,...
What each product offers, as listed by its team.


Possible disadvantages
Possible disadvantages
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
Overall verdict
Why this product is good
Recommended for
Walkthroughs and reviews on video.
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PostalDataPI Now Returns 18 Fields Per Postal Code — for 240+ Countries
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How often each product is chosen within a category, 0–100% relative to the other.


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Fast UK address, email & phone validation APIs for developers. Official Royal Mail PAF data. Pay as you go, 100 free lookups.
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