fill.dev

What It Is

fill.dev is a test website for browser and password manager autofill capabilities. The page states that it includes multiple forms for testing filling and saving behavior, and uses appropriate HTML autocomplete attributes for form elements where possible. It is not positioned as a full development platform, but rather as a lightweight, straightforward form compatibility testing tool.

Core Features and Ecosystem

The site covers a practical range of test scenarios, including Login, Simple HTTP Basic Auth, Registration, Email, Username, Email and Username, TOTP QR, Credit Card, Simple Identity, Search, and Save in 1Password. These are common scenarios for developers and QA teams working on password managers, browser autofill, identity autofill, and payment information autofill. The page also references the HTML Autofill Spec and the 1Password Developer Guide, indicating that its test design has some connection to web standards and the 1Password ecosystem.

Pricing and Deployment

The page does not mention any fees, subscriptions, enterprise plans, or payment information, so it appears that the current page can be accessed and used directly. However, its business model cannot be confirmed from the available information. There is also no visible open-source repository, self-hosting documentation, API, or SDK, so it is better understood as an online test page rather than an integrable developer service.

Pros and Cons

Its main advantage is simplicity: open the page and use sample data to test different types of forms. It also clearly notes that POST requests are not stored, while still recommending that users only use sample data, which reflects good security awareness. The downside is limited disclosure: there is no clear maintainer information, version history, automation interface, CI integration method, or detailed documentation. Teams that need large-scale regression testing may still need to build their own test pages or combine it with browser automation frameworks.

Who It’s For and Access from China

It is suitable for password manager vendors, browser teams, frontend developers, security engineers, and QA personnel who need to quickly verify autofill behavior, credential saving, TOTP, credit card forms, and identity forms. Access from mainland China cannot be determined from the page content and should be considered unknown. If access is unstable, alternatives include building a custom HTML autocomplete test page, referring to the HTML Autofill specification, or using the official developer guides provided by password manager vendors.