Software Alternatives, Accelerators & Startups

PostalDataPI VS Zipcodestack

Compare PostalDataPI VS Zipcodestack and see what are their differences

PostalDataPI logo PostalDataPI

The most affordable postal code API. 240+ countries, sub-5 ms responses. Simple, elegant, transparent.

Zipcodestack logo Zipcodestack

Free Zip Code API - Free Postal Code Validation | Zipcodestack
  • PostalDataPI Landing page
    Landing page //
    2026-04-08

PostalDataPI is a global postal code validation and enrichment API covering 240+ countries and territories. One API, one key, one flat rate โ€” $0.000028 per query with no tiers or subscriptions.

What you get back: Up to 18 metadata fields per postal code โ€” city, state/region, coordinates, timezone, three levels of administrative hierarchy, elevation, and more. Sub-5ms cached responses.

Works everywhere: US ZIP codes, UK postcodes, German PLZ, Japanese postal codes, Canadian FSAs, and 230+ more. Format normalization handles case, spacing, and hyphen variations automatically.

Get started in 60 seconds: 1,000 free queries on signup, no credit card required. SDKs for Python and Node.js. MCP server for AI agents (Claude, Cursor, etc.).

Built for developers: REST API, consistent JSON responses across all countries, OpenAPI spec, llms.txt for AI agent discovery.

Not present

PostalDataPI

$ Details
-
Platforms
-
Release Date
2026 March
Startup details
Country
United States
State
ID
City
Eagle
Founder(s)
Thom Ives
Employees
1 - 9

Zipcodestack

Pricing URL
-
$ Details
free
Platforms
REST API
Release Date
-

PostalDataPI features and specs

  • Specialized Postal Data
    PostalDataPI focuses specifically on postal and address-related data, providing dedicated endpoints for ZIP code lookups, address validation, and geographic postal information, making it a niche solution for mailing and logistics needs.
  • Simple API Integration
    The API appears to offer straightforward RESTful endpoints that are relatively easy to integrate into existing applications, requiring minimal setup and configuration for developers.
  • Useful for Address Validation
    The service can help businesses validate and standardize mailing addresses, reducing undeliverable mail, saving postage costs, and improving data quality in customer databases.
  • Geographic Data Enrichment
    PostalDataPI can enrich address data with additional geographic information such as coordinates, county, and timezone details associated with postal codes, which is valuable for analytics and location-based services.
  • Lightweight and Focused
    As a specialized micro-API, it avoids the bloat of larger platforms, offering a focused toolset that does one thing well โ€” handling postal and ZIP code data without unnecessary complexity.

Zipcodestack features and specs

  • Comprehensive Data Coverage
    Zipcodestack provides extensive data coverage for postal codes, allowing users to access detailed information about demographics, geography, and more.
  • Easy Integration
    The platform offers user-friendly APIs that make it easy to integrate postal code data into various applications, thereby simplifying the development process.
  • Real-time Updates
    Zipcodestack ensures that the data is constantly updated in real-time, providing users with the most accurate and current information available.
  • Customer Support
    Highly responsive customer support assists users with any issues or questions, ensuring a smooth user experience.

Possible disadvantages of Zipcodestack

  • Cost
    Some users might find the pricing model to be on the higher side, especially for small businesses or individual developers with limited budgets.
  • Learning Curve
    While the platform is comprehensive, it might require some time for new users to fully understand and utilize all its features effectively.
  • Dependency on Internet
    As an online platform, Zipcodestack requires a stable internet connection; disruptions in connectivity can impede access to data.
  • Limited Offline Functionality
    The platform has limited capabilities for offline use, which might be a drawback for applications requiring offline access to data.

Analysis of PostalDataPI

Overall verdict

  • I don't have verified, up-to-date information specifically about PostalDataPI (postaldatapi.com), including details on its accuracy, pricing, uptime, or customer reviews. I can't confirm whether it's a good product without more direct data or firsthand testing, so I'd recommend evaluating it yourself using the criteria below before committing.

Why this product is good

  • Unable to verify specific claims about data accuracy, coverage, or update frequency for this service
  • No confirmed information on pricing tiers, rate limits, or API reliability (SLA/uptime)
  • No verified user reviews, testimonials, or third-party comparisons available
  • Company background, support quality, and documentation quality are unconfirmed
  • If considering this service, check for: free trial/sandbox access, transparent pricing, data source citations, response time benchmarks, and independent reviews on sites like G2 or Trustpilot

Recommended for

  • Not able to make a specific recommendation without verified data
  • Best approach: developers needing postal/address validation APIs should compare this against established alternatives (e.g., SmartyStreets, Lob, Google Maps Geocoding API, USPS Web Tools) based on documented accuracy and pricing
  • Suitable evaluation candidates: teams willing to test the API directly with sample data before integrating into production systems

Analysis of Zipcodestack

Overall verdict

  • Zipcodestack is a solid, developer-friendly postal code lookup API that offers reliable geolocation and distance data with a straightforward integration process and a usable free tier, making it a good choice for adding zip code functionality to applications.

Why this product is good

  • Provides accurate postal code, city, state, and geolocation data across many countries
  • Offers a generous free tier that's great for testing and small projects
  • Simple REST API with clear documentation and easy authentication via API keys
  • Supports useful features like distance calculation between zip codes and radius searches
  • Fast response times and reliable uptime for production use
  • Affordable paid plans that scale with usage needs

Recommended for

  • Developers building location-based or address-validation features
  • E-commerce platforms needing shipping and delivery zone calculations
  • Startups and small businesses wanting an affordable postal code API
  • Applications requiring international zip code lookups and geocoding
  • Projects needing distance or radius-based search functionality between locations

PostalDataPI videos

PostalDataPI Now Returns 18 Fields Per Postal Code โ€” for 240+ Countries

More videos:

  • Tutorial - PostalDataPI Tutorial: Your First Postal Code API Call in 5 Minutes

Zipcodestack videos

No Zipcodestack videos yet. You could help us improve this page by suggesting one.

Add video

Category Popularity

0-100% (relative to PostalDataPI and Zipcodestack)
Geolocation API
100 100%
0% 0
APIs
0 0%
100% 100
Developer Tools
100 100%
0% 0
Data Validation
0 0%
100% 100

User comments

Share your experience with using PostalDataPI and Zipcodestack. For example, how are they different and which one is better?
Log in or Post with

Social recommendations and mentions

Based on our record, Zipcodestack seems to be more popular. It has been mentiond 3 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

PostalDataPI mentions (0)

We have not tracked any mentions of PostalDataPI yet. Tracking of PostalDataPI recommendations started around Apr 2026.

Zipcodestack mentions (3)

  • Validating Postal Codes Worldwide in Node.js โ€“ Challenges & Solutions with zipcodestack API
    Using the zipcodestack API in your Node.js application is straightforward. Youโ€™ll first need to sign up for a free API key (it only takes a minute). Once you have your API key, you can call the REST endpoints using any HTTP client. Below is a simple example using Nodeโ€™s built-in fetch (available in Node v18+), but you could use axios or any library of your choice:. - Source: dev.to / 10 months ago
  • A list of SaaS, PaaS and IaaS offerings that have free tiers of interest to devops and infradev
    Zipcodestack - Free Zip Code API and Postal Code Validation. Ten thousand free requests/month. - Source: dev.to / over 2 years ago
  • I have a column in google sheets with ZIP codes. How do i put a column next to it that will automatically fill with what city is associated with that zip code?
    I have seen this request pop up quite a few times. I did a quick search for free APIs of zipcode lookups. This one, named "zipcodestack" (I'm not in any way tied to, endorsing, or promoting them) seemed like a pretty good resource with up to 10,000 free lookups each month. So, I wrapped a quick script around it and made it a custom sheets function called GET_CITY:. Source: about 3 years ago

What are some alternatives?

When comparing PostalDataPI and Zipcodestack, you can also consider the following products

Smarty - Smarty provides address validation, autocomplete, geocoding and reverse geocoding services covering addresses in over 240+ countries.

ZIP Code API - REST API for US ZIP, ZIP+4, and Canadian postal codes. Single unified endpoint covers address validation and standardization, radius search (centroid haversine and true spatial polygon intersection), point-to-point distance, autocomplete/typeah

Melissa Data Quality - Melissa helps companies to harness Big Data, legacy data, and people data (names, addresses, phone numbers, and emails).

PostalCodes.info - Postal code lookup API and downloadable country datasets for address validation, checkout, logistics and geocoding workflows.