FusionAuth is a solid identity and access management (IAM) platform, and what stands out the most—what I “like best”—depends a bit on the use case, but here are the big highlights:

1. Developer-Friendliness: FusionAuth is built with developers in mind. It’s easy to install (via Docker or native install), well-documented, and has good SDKs for multiple languages. The API-first approach makes it very customisable.

2. Feature-Rich for Free Tier: The Community edition offers a surprising number of features out of the box—like OAuth2, OpenID Connect, SAML, 2FA, JWT support, and more—without needing a paid plan right away.

3. Self-Hosting Option: Unlike many identity providers that are strictly SaaS, FusionAuth lets you self-host. That’s huge for organisations that need control over data, want to comply with specific regulations, or just prefer managing their own stack.

4. Extensibility: You can add custom JWT claims, create custom user data fields, and even run Lambdas (small bits of custom code) during events like login or registration.

5. Migration & Import Tools: FusionAuth has robust tooling for migrating from other auth systems—super useful when switching from Auth0, Firebase, or a custom-built solution.

6. Multi-Tenant Support: If you’re building a SaaS platform, their multi-tenant support makes it easy to separate user bases across different organisations or applications. Review collected by and hosted on G2.com.

the admin UI can feel clunky and unintuitive at times, especially when configuring more advanced features like custom workflows or email templates. It works, but there’s a bit of a learning curve and some UX polish could go a long way.

Also, for very large-scale enterprise needs, you might hit some limitations unless you go with the paid version. Review collected by and hosted on G2.com.

What I love most about FusionAuth is how it brings together all the tools and platforms I need under one secure roof and as a result I no longer waste time hunting down login links or juggling a dozen passwords and everything I need is in one place. It’s easy to use, integrates seamlessly with other systems, and the browser extension makes starting my day effortless. I especially appreciate the ability to customize access depending on roles within the organization and something other tools like Okta and OneLogin struggled to handle as cleanly. Review collected by and hosted on G2.com.

One thing I wish FusionAuth handled better is session duration and I’d love the option to stay logged in for a defined number of days without being forced to reauthenticate so often. Occasionally, if a deployment isn’t planned well, it can feel overwhelming for new users to get the hang of. I’ve also noticed some limitations with integrating tools like Jira and Git, which competitors like Okta seem to support more readily. Review collected by and hosted on G2.com.

Comprehensive identity and access management solution – FusionAuth.

I've been using FusionAuth for nearly four years, and it stands out as a state-of-the-art solution. It seamlessly covers IAM/CIAM, offering various features that align perfectly with our requirements. I also appreciate the team's proactive approach in providing education and addressing priority concerns whenever we reach out.

We never had a downtime or an impact for login functions after using FusionAuth. Review collected by and hosted on G2.com.

Changing the front-end / UI reuqires a special skillsets or work with a few vendors. This could have been simplified.

Plug and play for a layman to deal with security, IAM. Review collected by and hosted on G2.com.

FusionAuth positions itself as a highly flexible and developer-centric identity and access management (IAM) solution. It offers a compelling alternative to more established players, especially for teams that prioritize data ownership, customization, and a transparent pricing model for advanced features. While it might not have the out-of-the-box UI polish of some competitors, its raw power and self-hosting capabilities make it a strong contender for a wide range of applications, from startups to enterprises. Review collected by and hosted on G2.com.

Admin UI/UX: While functional, the admin UI can feel a bit dated and less intuitive compared to the slick dashboards of Auth0 or Clerk. Finding certain settings or configuring advanced workflows can sometimes require a bit of digging through documentation.

Theming Customization Complexity: While powerful, fully customizing the look and feel of the hosted login pages to perfectly match your brand can be more involved than with solutions that offer more WYSIWYG or component-based theming.

Fewer "Out-of-the-Box" Pre-built UI Components: Unlike Clerk, which excels here, FusionAuth provides the backend and APIs, but you'll be building more of the frontend integration yourself (or using their base themes which might need more tweaking). Review collected by and hosted on G2.com.

It gives me full control over user management without forcing me into a specific workflow. The documentation is clear and the admin dashboard is easy to navigate. I like that it supports multiple authentication methods like OAuth, SAML, and passwordless so I can adapt it for different clients. Review collected by and hosted on G2.com.

The initial setup takes some patience especially if you are hosting it yourself. Some advanced configurations feel a bit buried in the settings. Review collected by and hosted on G2.com.

I love that it is developer-oriented and super flexible. Usually, any of the competitors are extremely expensive and difficult to use, but FusionAuth makes things super smooth and easy to implement. We have utilized the Terraform integration to deploy it, making our infrastructure easier to maintain and develop.

When it comes to users, it is a smooth integration that allows the user to authenticate from any of our platforms with ease and provides all the authentication methods that we would need. We primarily use magic links to avoid using passwords, and the integration was very straightforward forward and it works like a charm.

They also provide third-party integrations, such as Kafka, that make integration with the rest of our infrastructure extremely straightforward, allowing us to utilize what we already have.

Their customer support is great, we have only had great experiences when we need to contact them.

We have more than 20,000 users and around 4,000 monthly active users, and have used this product in production for more than 4 years. Review collected by and hosted on G2.com.

Because FusionAuth is so developer-oriented, the integration with templates and UI is very complicated. There's no easy way to implement a custom theme, so it is easier to create a custom solution that uses their internal system. UX is not the best with their default system, so it's better to steer away from that completely.

It would be awesome if they allowed some kind of infrastructure peering to make the integration with existing cloud infrastructure easier and more secure without having to deploy our self-managed instance. Review collected by and hosted on G2.com.

FusionAuth makes it easy to add safe and secure auth in a way where I don't have to worry about the pitfalls of writing our own security. I especially like how all the edge cases are considered, and "nice to have" features such as rate limiting, CAPTCHA, and social login in is just a single click to enable. It has thorough API documentation that makes it easy to implement as well as several client libraries for all the platforms we used. Support has been excellent and helped us with many problems. I love that it can be self hosted, so we can set up systems locally for development and testing. Review collected by and hosted on G2.com.

FusionAuth lacks documentation on the client libraries, although thankfully they're mostly wrappers of the API so documentation can be gleamed. FusionAuth also has a gap between "easy" things and "difficult" things. Ie, once you need a single feature beyond what a Simple Theme can provide, it requires converting the whole thing to advanced themes.

Support is not very active in the development, as evidenced by the number of open issues on Github which haven't been addressed in years. Review collected by and hosted on G2.com.

FusionAuth made it easy to implement secure authentication with minimal friction and maximum control. Review collected by and hosted on G2.com.

FusionAuth strikes a rare balance between ease of use and deep customizability. The documentation is thorough, the APIs are well-structured, and the admin UI is intuitive. Unlike many other identity platforms, FusionAuth gives you full control over the user data and the infrastructure — which is invaluable when you need compliance, security, or performance tuning. Review collected by and hosted on G2.com.

FusionAuth stands out as a developer-friendly identity and access management (IAM) platform that excels in ease of integration, flexibility, and multi-tenancy—qualities especially valuable for SaaS providers. I really like the SaaS offering with its development friendly pricing with option to upgrade for a more enterprise level of scalability and availability.

Administration of the SaaS instance is headache free with option to update FusionAuth by a "single" button with a minimal downtime.

IAM admin panel have nice UI/UX which was important at beginning of our IAM adventure because we did not have enough time to integrate IAM admin panel into our application. Review collected by and hosted on G2.com.

It would be nice to integrate FusionAuth SaaS offering into our monitoring and uptime tracking solutions. Right now we do not see easy solution for this.

Our custom workflows required to write a library to ensure no possibility of making mistakes when integrating it in our modular backend application. Review collected by and hosted on G2.com.

I really appreciate the customization FusionAuth brings to the table - it’s a standout feature that gives you the flexibility to mold it to your specific needs. The model is well-designed, and the feature set is impressive, covering a lot of bases for authentication and user management. It feels developer-friendly, which makes integration into projects smoother and more enjoyable. Review collected by and hosted on G2.com.

Despite its strengths, there are some frustrating drawbacks. The API breaking between releases is a big issue - it’s disruptive and adds unnecessary rework. I also found the authorization customization lacking; there’s no easy way to implement permission-based or attribute-based authorization, which feels like a missed opportunity for a service like this. On top of that, the API can be unreliable. For example, when deleting a user from a group, I’ve seen inconsistent results—sometimes it removes their roles, sometimes it doesn’t, and it’s unpredictable. These issues make it harder to rely on consistently. Review collected by and hosted on G2.com.