
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.

Treehouse
edX
Docebo
Pluralsight
Khan Academy
Talent LMS
Codecademy
The ClassMarker online testing website, is a professional, easy to use, online quiz maker that marks your tests and quizzes for you. Create online quizzes free quiz maker. Web-based online testingWeb-based online testing service | Free quiz maker.

Which is more popular?
Website, pricing, platforms and company facts side by side.
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| Website | postaldatapi.com | classmarker.com |
| Pricing | ||
| Company | Startup from the United States · 1 - 9 employees · 2026 | — |
| Listed in |
In their own words, as submitted to SaaSHub.


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,...
No description of ClassMarker yet.
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
ClassMarker is recommended for educators, trainers, and businesses seeking an efficient way to manage online assessments. It's particularly useful for teachers conducting exams, HR professionals managing employee evaluations, and trainers delivering certification tests.
Walkthroughs and reviews on video.
PostalDataPI Now Returns 18 Fields Per Postal Code — for 240+ Countries
More videos
How to Use ClassMarker - A Free Online Test Maker
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How often each product is chosen within a category, 0–100% relative to the other.


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External articles and on-site reviews we used to compare the two products.


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ClassMarker is yet another online test maker tool that offers secure, professional web-based online testing solutions for business, training & educational assessment. It is easy to use and offers several customization...
ClassMarker is another all-in-one quizzing solution on our list. It’s a cloud-based test builder that can be used by instructors and online storage for published assessments that students can log in to and take...
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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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Treehouse is an award-winning online platform that teaches people how to code.
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We help businesses improve UX and data quality with a cutting edge address validation service.
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Best Courses. Top Institutions. Learn anytime, anywhere.
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Fetchify delivers fast, accurate address, email, phone and bank validation tools that help businesses capture clean, verified customer data, reduce failed deliveries and improve checkout experiences worldwide.
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Docebo Learning Management System is the best cloud LMS system on the market for online training. AICC SCORM xAPI compliant. Mobile elearning platform
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