Software Alternatives & Startups

ZIP Code API VS Postio.co.uk

Compare ZIP Code API VS Postio.co.uk and see what are their differences

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

Rating
0 reviews
Postio.co.uk

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

Rating
0 reviews
Pricing
Paid Free trial £0.02 (Address 2.2p (searching is free), Email & Phone 1p)
Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Which is more popular?

APIs popularity
100% vs 0%
alternatives listed
7 vs 11

Base details

Website, pricing, platforms and company facts side by side.

ZIP
ZIP Code API
Postio.co.uk
Website zip-codes.com postio.co.uk
Pricing —
Paid Free trial £0.02 (Address 2.2p (searching is free), Email & Phone 1p) Official pricing
Platforms —
REST API Web JavaScript Node JS Python Go PHP Ruby .Net Wordpress Zapier +8
Company Startup from the United States · 2026 Startup from the United Kingdom · 1 - 9 employees
Listed in

About ZIP Code API and Postio.co.uk

In their own words, as submitted to SaaSHub.

ZIP
ZIP Code API
Postio.co.uk

API for US ZIP, ZIP+4, and Canadian postal code data. One unified endpoint set covers North America — no separate APIs by country or data type. What it does Address validation and standardization — production-grade parser with ZIP+4 append, refreshed monthly Radius search — centroid haversine and...

Read more about ZIP Code API

Postio (postio.co.uk) is a developer-focused data validation platform providing real-time UK address lookup, email verification, and phone validation via plain REST APIs and drop-in SDKs. As an official Royal Mail PAF Solutions Provider, Postio synchronises 30M+ UK addresses daily for accurate...

Read more about Postio.co.uk

Features and specs

What each product offers, as listed by its team.

ZIP
ZIP Code API 5 features
Postio.co.uk 9 features
  • Comprehensive ZIP Code Data
    The ZIP Code API from zip-codes.com provides extensive data including ZIP code details, city information, state data, and geographic coordinates, making it a thorough resource for location-based lookups.
  • Multiple Lookup Options
    The API supports various types of lookups including ZIP code to city/state, city/state to ZIP code, distance calculations between ZIP codes, and radius searches, offering flexible querying capabilities.
  • Easy Integration
    The API uses standard REST-based HTTP requests and returns data in commonly used formats like JSON and XML, making it straightforward to integrate into most applications and programming languages.
  • Distance and Radius Calculations
    The API includes built-in functionality for calculating distances between ZIP codes and finding ZIP codes within a specified radius, which is valuable for store locators, shipping estimates, and proximity-based features.
  • Well-Documented Endpoints
    The API provides clear documentation for its various endpoints and parameters, helping developers understand available features and implement them correctly without extensive trial and error.
  • Address search
    UK address typeahead over Royal Mail PAF data, held under a direct licence
  • Postcode lookup
    Every PAF delivery point at a given postcode
  • UDPRN lookup
    Full address record by Royal Mail Unique Delivery Point Reference Number
  • Email validation
    Syntax, typo correction, MX, SMTP check and deliverability classification
  • Phone validation
    Parse and validate, plus live HLR lookup for carrier, ported status and reachability
  • Pricing model
    Pay per request — 2.2p per address, 1p per email, 1p per phone. No tiers, no contracts
  • Free tier
    100 lookups, no card required
  • API design
    All endpoints are GET and return the same JSON envelope. Public OpenAPI spec, CORS enabled
  • SDKs and integrations
    Official SDKs for JavaScript/Node, Python, Go, PHP, Ruby and .NET. Drop-in browser widget (~4 KB gzipped), MCP server for AI agentsOfficial SDKs for JavaScript/Node, Python, Go, PHP, Ruby and .NET. Drop-in browser widget (~4 KB gzipped), MCP server for AI agents

Analysis

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

ZIP
ZIP Code API
Postio.co.uk

Overall verdict

  • ZIP Code API from zip-codes.com is a solid, reliable choice for developers and businesses needing accurate US and Canadian postal code data, offering a straightforward RESTful interface with regularly updated databases.

Why this product is good

  • Provides accurate and frequently updated ZIP code, city, state, and geographic data
  • Offers a simple RESTful API that is easy to integrate into web and mobile applications
  • Supports features like ZIP code lookup, radius search, and distance calculations
  • Includes both US ZIP codes and Canadian postal codes for broader coverage
  • Backed by an established data provider with a long track record in postal data

Recommended for

  • Developers building address validation or autofill features
  • E-commerce platforms needing shipping and location-based calculations
  • Businesses performing geographic or radius-based store locators
  • Applications requiring reliable US and Canadian postal data
  • Marketing and logistics teams that need regional or demographic targeting

No analysis of Postio.co.uk yet.

Category popularity

How often each product is chosen within a category, 0–100% relative to the other.

Score bands 0–20 21–40 41–50 51–60 61–100
ZIP
ZIP Code API
Postio.co.uk
100% 100%
0% 0%
0% 0%
100% 100%
100% 100%
0% 0%
0% 0%
100% 100%

Questions & Answers

As answered by people managing ZIP Code API and Postio.co.uk.

What makes your product unique?

Postio.co.uk's answer:

Postio charges only when a lookup returns a result — searching is free. Address, email and phone validation sit behind one API with a single JSON response envelope, so you integrate once rather than stitching three vendors together. Address data comes from Royal Mail's Postcode Address File under a direct licence, not scraped or resold sources. There are no tiers, contracts or minimum spend, and the first 100 lookups need no card.

Which are the primary technologies used for building your product?

Postio.co.uk's answer:

A REST API served from edge locations, with official SDKs for JavaScript/Node, Python, Go, PHP, Ruby and .NET, all open source on GitHub. The API is documented by a public OpenAPI specification.

Why should a person choose your product over its competitors?

Postio.co.uk's answer:

Pricing is published and pay-as-you-go: 2.2p per address, 1p per email, 1p per phone, billed only on a result. No sales call, no annual contract, no minimum commitment. You can be live in a few minutes with 100 free lookups and no card, and the same API covers all three validation types. For UK addresses specifically, the data is licensed directly from Royal Mail rather than obtained second-hand — which matters after the 2025 High Court ruling on database rights in this market.

How would you describe the primary audience of your product?

Postio.co.uk's answer:

Developers and technical teams building UK-facing forms — ecommerce checkouts, signup flows, CRM and logistics systems. Typically small to mid-sized product teams, agencies building for UK clients, and software vendors embedding address lookup in their own product. It suits anyone who wants a UK-accurate API without an enterprise procurement process.

What's the story behind your product?

Postio.co.uk's answer:

Postio is a trading name of Onno Group Limited, registered in England & Wales (company no. 08622799). It was built to make Royal Mail PAF-accurate UK validation available on straightforward pay-as-you-go pricing, rather than the contracts and minimum commitments that have been standard in this market. Address, email and phone validation were brought together behind one consistent API so a team can solve all three at once.

Who are some of the biggest customers of your product?

Postio.co.uk's answer:

Serving a huge range of customers across the world looking for a blazing fast UK Address AIP product. From bootsrapped entrepreuners to FTSE 250 companies. We serve them all.

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