Software Alternatives & Startups

IsValid.dev VS Postman

Compare IsValid.dev VS Postman and see what are their differences

IsValid.dev

A powerful REST API for validating emails, IBANs, BIC/SWIFT codes, LEI, ISIN, credit cards, VAT numbers, phone numbers, and 70+ more validators. Free tier available.

Rating
0 reviews
Pricing
Freemium Free trial €9 / Monthly (10000 API calls / day)
Postman

The Collaboration Platform for API Development

Rating
0 reviews
Pricing
Open source

Which is more popular?

Based on our record, Postman seems to be more popular. It has been mentioned 30 times since March 2021.

social mentions
0 vs 30
APIs popularity
1% vs 99%
alternatives listed
11 vs 240+

Base details

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

IsValid.dev
Postman
Website isvalid.dev postman.com
Pricing
Freemium Free trial €9 / Monthly (10000 API calls / day) Official pricing
Open source
Platforms
Python Node JS Wordpress
Windows Mac OSX Linux
Company — Startup from India
Listed in

About IsValid.dev and Postman

In their own words, as submitted to SaaSHub.

IsValid.dev
Postman

IsValid is a validation API service for developers who need to quickly verify data formats without building their own validators. It offers 40+ endpoints covering financial identifiers (IBAN, BIC, ISIN, CUSIP), international standards (ISBN, ISSN), technology formats (UUID, JWT, QR codes),...

Read more about IsValid.dev

No description of Postman yet.

Features and specs

What each product offers, as listed by its team.

IsValid.dev 5 features
Postman 6 features
  • Lightweight schema validation
    IsValid.dev offers a minimal, lightweight approach to schema validation for TypeScript, avoiding the bloat that can come with larger validation libraries.
  • TypeScript-first design
    Built with TypeScript in mind, providing strong type inference so validated data automatically gets proper TypeScript types without extra manual typing.
  • Simple API
    The library offers an intuitive and easy-to-learn API for defining and running validations, making it accessible for developers to quickly get started.
  • Zero or minimal dependencies
    Being a lightweight tool, it typically has little to no external dependencies, reducing bundle size and potential security/maintenance issues from third-party packages.
  • Good for small to medium projects
    Its simplicity makes it well suited for smaller projects or use cases where heavier libraries like Zod or Yup might be overkill.

Possible disadvantages

  • Smaller community and ecosystem
    Compared to established validation libraries like Zod, Joi, or Yup, IsValid.dev has a much smaller user base, meaning fewer community resources, tutorials, and third-party integrations.
  • Limited documentation
    As a newer or less mainstream tool, its documentation may be less comprehensive than more established alternatives, making it harder to find answers to edge-case questions.
  • Fewer advanced features
    It may lack some of the advanced features found in more mature libraries, such as extensive built-in validators, custom error message localization, or complex schema composition tools.
  • Less battle-tested
    Being less widely adopted, it may not have been tested against as many real-world edge cases as more popular libraries, potentially leading to undiscovered bugs.
  • Uncertain long-term support
    Newer or niche libraries carry a higher risk of reduced maintenance or discontinuation over time compared to well-funded or widely-adopted projects.
  • User-Friendly Interface
    Postman features an intuitive and user-friendly interface that simplifies the process of constructing API requests and visualizing responses. This makes it accessible for both beginners and advanced users.
  • Collaboration
    Postman offers robust collaboration features, such as shared workspaces, collections, and real-time editing, enabling teams to work together more efficiently on API development.
  • Comprehensive Testing Tools
    Postman provides a suite of testing tools to create, automate, and manage test cases. It supports automated testing through its scripting environments, which ensure APIs perform as expected.
  • Extensive API Documentation
    Postman can automatically generate comprehensive API documentation, making it easier to maintain and share API specifications with stakeholders and other developers.
  • Mock Servers
    Postman allows users to create mock servers to simulate API responses. This is particularly useful for testing and development purposes when the actual API is not yet available.
  • Integration Capabilities
    Postman offers integrations with various CI/CD tools, version control systems, and other services like Jenkins, GitHub, and Slack, facilitating seamless integration into development workflows.

Possible disadvantages

  • Resource Intensive
    Postman can sometimes be resource-intensive, consuming substantial memory and CPU, which can impact the performance of your system, especially when dealing with large collections.
  • Steep Learning Curve for Advanced Features
    While Postman is generally user-friendly, some of its advanced features, like scripting and automation, can have a steep learning curve and might require additional effort to master.
  • Pricing
    Although Postman offers a free tier, many of its advanced features, such as enhanced collaboration tools and extended integrations, are locked behind paid plans, which may not be cost-effective for smaller teams or individual developers.
  • Dependency on Internet
    Some of Postman's features, particularly those related to collaboration and synchronization, require a stable internet connection, which can be a limitation in environments with poor connectivity.
  • Limited Native Support for Certain Protocols
    Postman primarily focuses on HTTP/HTTPS protocols and may offer limited or no native support for other protocols, which can be restricting for developers working with diverse sets of technologies.

Analysis

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

IsValid.dev
Postman

Overall verdict

  • IsValid.dev appears to be a developer-focused validation/utility tool that can be useful for quick, lightweight validation tasks, though I don't have verified, up-to-date details on its full feature set or reliability track record.

Why this product is good

  • Likely offers a simple, developer-friendly interface for validation tasks
  • Probably free or low-cost, making it accessible for quick checks
  • May support common validation formats (e.g., JSON, schemas, or data formats) useful in development workflows
  • Could save time compared to writing custom validation scripts for simple use cases

Recommended for

  • Developers needing quick, ad-hoc validation checks
  • Small projects or prototypes where a lightweight tool suffices
  • Users looking for a free or low-cost alternative to more complex validation suites
  • Learning or testing purposes rather than mission-critical production validation

Overall verdict

  • Yes, Postman is widely regarded as a good tool for API development and testing. Its combination of powerful features and ease of use makes it a popular choice among developers.

Why this product is good

  • Postman is considered a top choice for API development due to its user-friendly interface, extensive features for testing, automation, and collaboration, and strong community support. It simplifies the process of creating, managing, and testing APIs, making it accessible for both beginners and experienced developers.

Recommended for

  • Developers working on API integration
  • QA engineers involved in testing APIs
  • Teams in need of collaborative API development
  • Developers looking to automate API testing
  • Individuals looking for a comprehensive API testing tool

Videos

Walkthroughs and reviews on video.

IsValid.dev 0 videos + Add
Postman 3 videos + Add

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

POST/CON 2018 workshop in review: Running Postman Collections

More videos

  • - POST/CON 2018 workshop in review: Postman Collections
  • - How to Share Postman Collections

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
IsValid.dev
Postman
1% 1%
99% 99%
1% 1%
99% 99%
100% 100%
API
0% 0%
1% 1%
99% 99%

Questions & Answers

As answered by people managing IsValid.dev and Postman.

What makes your product unique?

IsValid.dev's answer

IsValid offers 70+ validators in a single API — covering financial identifiers (IBAN, BIC, ISIN, LEI), international standards (ISBN, ISSN), technology formats (UUID, JWT, QR codes), tax numbers (VAT, REGON, PESEL), credit cards, phone numbers, and more. No need to integrate multiple services for different data types.

Why should a person choose your product over its competitors?

IsValid.dev's answer

Most validation APIs focus on one category (email or phone). IsValid covers financial, regional, and technical formats all in one place with a consistent REST API. The free tier with 100 calls/day requires no credit card, and integration takes minutes.

How would you describe the primary audience of your product?

IsValid.dev's answer

Developers and software teams building applications that handle user input, financial data, or international identifiers — particularly in fintech, e-commerce, and SaaS products.

What's the story behind your product?

IsValid.dev's answer

IsValid was built out of frustration with piecing together multiple validation libraries and services. The goal was a single, reliable API that handles the full range of data validation needs developers encounter in real-world applications.

Which are the primary technologies used for building your product?

IsValid.dev's answer

Next.js, Fastify, PostgreSQL, Docker

User comments

Share your experience with using IsValid.dev and Postman. For example, how are they different and which one is better?

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Reviews and articles

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

IsValid.dev no reviews yet
Postman no reviews yet

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Social recommendations and mentions

Recommendations tracked on public social media and blogs since March 2021.

IsValid.dev 0 mentions
Postman 30 mentions

Tracking IsValid.dev since Apr 2026.

  • Best API Mocking Platforms in 2024
    Postman (postman.com) is a comprehensive API platform that goes beyond mocking, offering a full suite for API development, testing, and monitoring. With its mock server feature, Postman enables teams to simulate responses for various... - Source: dev.to / almost 2 years ago
  • 10 Best API Mocking Tools (2024 Review)
    Postman is a widely used tool for API testing and interaction. Its "Mock Servers" feature lets you create a mock version of your API, returning specific responses for testing. While useful, Postman may lack advanced mock server... - Source: dev.to / almost 2 years ago
  • The 3 Best Tools for API Design for Software Architects
    Postman is a widely adopted tool for API design and development, offering an intuitive interface for creating, testing, and documenting APIs. It simplifies the API design process, allowing architects to quickly prototype and refine their... - Source: dev.to / about 2 years ago

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Alternatives to IsValid.dev and Postman

When comparing IsValid.dev and Postman, you can also consider the following products.