Test File Injector

About

Test File Injector lets you inject test files directly into file upload fields on any website, without opening a file picker or manually selecting a file each time.
Built for developers and QA engineers who repeatedly test file upload functionality.

How it works
Click on any file upload field and Test File Injector intercepts it, showing you a small modal where you can choose what to inject. Confirm, and the file is placed directly into the field, ready to submit.

Two modes
1. Generated files: Instantly create a PDF, CSV, or PNG at a precise target size. Useful for testing size limits, validation logic, or server-side processing without needing real files on hand.
2. Saved presets: Upload any real file once and save it as a preset. From then on, inject it into any upload field with two clicks. Presets are stored locally in your browser and persist across sessions.

Auto-Upload mode
Skip the modal entirely. When enabled, the active preset is injected immediately when you click an upload field, no confirmation required. Ideal for repetitive testing workflows.

Privacy
No data ever leaves your browser, except for the test files you deliberately inject into upload fields. Those are submitted to the website you are testing, as intended. All extension settings and saved presets are stored locally using Chrome's built-in storage. No tracking, no analytics, no external servers.