Retool alternative · for Rails teams

Your admin belongs in your Rails app, not another platform.

If your product runs on Rails, your internal tools can live there too. Avo is an admin framework that runs inside your app: it uses the models, validations, and policies you already trust, ships through the git workflow you already use, and adds your whole team for one per-app price.

For Rails teams weighing Retool, or already paying for it and watching the per-seat bill climb as the team grows.

250+ paying companies run on Avo  ·  2.7M downloads of the avo gem

01 · credit where it's due

Retool is a good product, for a different job.

Retool is one of the strongest hosted internal-tool builders out there. It shines when you need to pull many different data sources, several databases, third-party APIs, SaaS tools, into one place and assemble a tool by dragging components around. It doesn't care what your backend is written in, and people who aren't Rails developers can build with it.

If that's the problem in front of you, Retool is a fair choice and the rest of this page won't change your mind. But if your product is a Rails app, a lot of what you pay Retool for is work your codebase has already done.

02 · the core difference

A hosted app builder, or an engine in your repo.

Retool is a platform you build on top of: your tools live in Retool's editor and reach your data through connectors. Avo is a Rails engine you mount inside the app you already have. That one structural choice is where every other difference comes from. It's the same reason every product is really two apps, the one your customers see and the internal one behind it, and why the second one doesn't need to be a separate platform.

Retool

A separate platform

Built in a hosted editor, reaching your database through connectors, priced by the head.

Avo

Inside your Rails app

A mounted engine that reads your models directly, ships in your deploy, and adds no new seat to buy.

a

It lives in your codebase

Avo runs inside your Rails app, so your data never leaves it. There's no third-party service sitting between your team and your database, and nothing new to add to your security review.

b

No black box, no lock-in

When you hit the edge of what's built in, you drop down to plain Rails instead of filing a feature request and waiting on a vendor. You're never stuck with what someone else decided to support.

c

One mental model

Your whole admin shares Avo's conventions and your app's own code, instead of being a separate UI bolted onto your data. Any Rails developer who knows Avo is productive on day one.

03 · side by side

The same job, measured two ways.

An honest read, Rails team to Rails team. Retool is capable on every row; the question is how much of it you should have to run as a second system.

Avo Retool
Where it runs
AvoA Rails engine mounted in your app, deployed with it.
RetoolA hosted platform, or self-hosted with Docker in your own VPC.
Your models, validations, and policies
AvoReused directly, including the authorization rules you already wrote.
RetoolReimplemented in the app builder and its query layer.
How changes ship
AvoAs code in your repo, through pull requests and code review.
RetoolIn the hosted editor. Git-based source control is a paid higher-tier feature.
Pricing model
AvoPer app, with unlimited users. The bill doesn't move when you hire.
RetoolPer builder plus per end user, $10 to $50 per builder per month (as of July 2026), so the cost grows with the team.
When you hit an edge
AvoDrop to plain Rails, ViewComponent, and Stimulus, tools you already use.
RetoolCustom components and code exist, but you stay inside Retool's runtime.
Where your data lives
AvoIn your own database, reached the same way your app reaches it.
RetoolReached through connectors. Self-hosting keeps it on your infrastructure.

04 · it's just Ruby in your repo

This is a working admin for a model.

No editor to log into, no connector to configure. You write a Ruby class, commit it, and it ships in your next deploy. Here is the entire admin for a User:

# app/avo/resources/user.rb
class Avo::Resources::User < Avo::BaseResource
  self.model_class = "User"

  def fields
    field :id, as: :id
    field :name, as: :text
    field :email, as: :text
    field :admin, as: :boolean
    field :projects, as: :has_many
  end
end

Add a field, open a pull request, and a teammate reviews the diff before it reaches production, the same review that catches a missing scope or a dropped policy. Your whole team gets the screen, and there's no seat to buy for the next hire. See the full resource DSL in the Avo docs.

05 · when Retool wins

When we'd point you to Retool instead.

We would rather you use the right tool than the one we make. Reach for Retool when:

  • Your stack isn't Rails, or you're stitching tools across several different backends.
  • The tool needs to sit on top of many heterogeneous data sources at once: multiple databases, third-party SaaS APIs, spreadsheets.
  • The people building the internal tools aren't Rails developers, and you want them assembling screens without touching the codebase.
  • You want a fully hosted platform where your team maintains none of the plumbing.

If none of those describe you and your product is already a Rails app, the admin doesn't need to be a second platform. Moving an existing internal tool over is its own project, and we've written up how we think about rewriting your admin.

Frequently asked questions

Is Avo a good Retool alternative for Rails apps?
Yes, if your product is built on Rails. Avo is an admin framework that runs inside your Rails app instead of on a hosted platform, so your internal tools share the models, validations, and authorization you already wrote. You get the convenience of buying an admin without moving your back office onto someone else's service.
Does Avo charge per seat like Retool?
No. Retool prices per builder and per end user, $10 to $50 per builder per month as of July 2026, so the bill grows as your team does. Avo 4 is priced per app with unlimited users, so you can add your whole team, and every future hire, without watching the cost scale with headcount. See the Avo pricing page for the current plans.
Can I self-host Avo?
Avo isn't hosted anywhere to begin with. It's a Ruby gem that runs inside your own Rails application, so it deploys wherever your app already runs and reads your database the same way your app does. There's no separate service to host, and your data never leaves your infrastructure.
How is Avo structurally different from Retool?
Retool is a hosted app builder: your tools live in its editor and reach your data through connectors. Avo is a Rails engine you mount inside your existing app. Because it's part of your codebase, changes ship as code through git and code review, and when you hit an edge you drop to plain Rails instead of filing a feature request.
Do admin screens built with Avo go through code review?
Yes. An Avo resource is a Ruby class in your repository, so a change to your admin is an ordinary pull request. A teammate reviews the diff before it reaches production, the same review that catches a missing scope or a dropped policy. Retool offers git-based source control too, but as a paid higher-tier feature rather than the default way changes ship.
When is Retool the better choice than Avo?
When your stack isn't Rails, when you need to combine many heterogeneous data sources (several databases, third-party SaaS APIs) into one tool, or when the people building the tools aren't developers and you want a fully hosted platform. Retool is a strong product for those situations, and we'd rather you use the right tool for the job.
Can I move off Avo later without a rewrite?
Avo is built on tools you already use, ViewComponent, Stimulus, and Hotwire, and it gives you escape hatches to replace parts of it with your own code as you go. Because it's plain Rails underneath, there's no proprietary format to export from and no vendor to migrate away from. You can compare it with other Rails admins on the Avo alternatives page.

→ keep it in your codebase

Your admin belongs in your Rails app.

Start a free trial and mount Avo in your app in an afternoon. Per-app pricing, unlimited seats, and it's your Rails code the whole way down.