Browser Kitty
日本語
Browser Kitty

About

Browser Kitty publishes practical browser-based tools for PDFs, images, video, data inspection, and everyday tasks, together with guidance on how to use them and where their limits are.

About Browser Kitty

Browser Kitty turns tasks involving PDFs, images, video, data inspection, and everyday work into practical browser-based tools, especially when installing dedicated software would be unnecessary or inconvenient.

Where a tool supports it, files and entered content are processed in the browser rather than sent to a Browser Kitty backend. No account registration is required.

Why build for the browser?

Some tasks are useful only occasionally and do not justify installing a dedicated application: rearranging PDF pages, cutting a section from a video, inspecting a SQLite database, or checking location metadata in a photo.

Browser Kitty aims to make those tasks available by opening a URL when needed. Using the browser as a common runtime also makes the same tools easier to reach from desktop and mobile devices.

Use the browserPrefer tools that work without installation
Process locally when possibleKeep files and input on the device where the tool supports it
Keep the use case concreteMake it clear what task each tool is intended to solve
Publish the codeMake each tool's source available for inspection on GitHub

Local processing matters

For file-based tools, Browser Kitty tries to keep processing inside the browser. Supported image conversion, PDF processing, video operations, and SQLite inspection work without uploading the selected file to a Browser Kitty backend.

Local processing also has limits. Speed and practical file size depend on the device, available memory, and browser implementation. Some operations can be slower than services backed by large servers, and capabilities can differ between devices. Tool pages therefore describe both supported workflows and known limitations as specifically as possible.

From single actions to complete workflows

Browser Kitty started mainly with relatively simple tools that convert, rearrange, or inspect something. More recent tools increasingly cover the steps that come after opening a file or starting a task, so more of the workflow can be completed in the browser.

Process filesCompare output choices and adjust the result, as in Image Compressor & Converter. Inspect and understandGo beyond opening a file with search, relationships, and health checks, as in SQLite Explorer. Organize everyday workUse the browser for non-conversion workflows too, as with Task Packing and Restock List.

The goal is not to add features for their own sake. The main question is how much of the intended task a person can reasonably finish after opening the tool.

The single-HTML approach

As a general rule, Browser Kitty tools are designed so that, where practical, they remain easy to handle as a single HTML file. Using the browser as the common runtime reduces dependence on a particular desktop application or cloud service and makes saved tools easier to keep and use in your own environment.

Not every tool has exactly the same structure because some operations depend on particular browser capabilities or additional runtimes. Requirements and limitations are documented on each tool page and in its GitHub repository.

Guides as well as tools

A tool by itself does not always explain when it is appropriate, what file-format differences matter, or where the pitfalls are. Browser Kitty therefore publishes practical guides alongside the tool pages.

The guides cover not only button-by-button instructions but also cases where another method may be better, what stays local, and limitations created by file formats or processing methods. The aim is to leave enough information to make a reasonable decision about the task, not merely to promote use of a tool.

How tools and guides are published

Browser Kitty publishes tools after building and checking the actual implementation, then uses practical guides to explain how those tools can be used. The goal is not simply to increase the number of pages, but to keep the published explanation aligned with what the current implementation actually does.

Tools

Before release, checks cover core operation on desktop and mobile, Japanese and English layouts, file loading and saving, and guidance for empty, completed, and error states. When a tool is described as fully local, the release check also covers whether user files or entered content are sent outside the app.

Guides

Guides are based on the current behavior of tools that are actually published. Where useful, they also state unsupported cases, limitations, and cautions rather than describing features the tool does not provide. Relevant guides link to the real tool or its detail page.

Updates

Tools continue to receive bug fixes and usability improvements after release. When a specification change makes a guide outdated, the guide is updated as needed. Source code and development history for individual tools are generally available on GitHub.

AI may be used to assist development or writing. Even when it is used, descriptions of tool specifications, actual behavior, and privacy are checked against the implementation that is actually published.

Open source

Source code for each Browser Kitty tool is published on GitHub. You can inspect how a tool processes data or use the code in your own environment. See the individual repository for its license.

View GitHub

Operator

Browser Kitty is developed and operated by independent developer Tomohisa Takagi. The tools are based on things I want to use myself or tasks that otherwise take more steps than they seem to require, with an emphasis on reducing those steps and keeping the work in the browser.

Source code and development activity for the tools are published on GitHub.