In-Browser ID Document Watermarker

Watermark your ID and passport photos without uploading anything

Problem

Renting an apartment, opening an account, or applying for a visa often requires uploading a copy of your ID. Handing over the original image exposes your identity, and most online watermark tools require uploading the file, which defeats the purpose.

Solution

A purely client-side web tool: drag in an image and generate a version with custom text (e.g. 'for X use only'), date, and diagonal pattern, all processed locally. Neither the original nor the watermarked image leaves the browser. Supports batch processing, PDF export, and optional redaction of sensitive fields.

Users

Anyone frequently submitting ID copies, people dealing with visas, rentals or bank onboarding, and privacy-conscious freelancers or small business admins.

MVP

Drag-and-drop upload; customizable watermark text, angle, opacity, density; one-click export of watermarked image; rectangle redaction tool; clear statement that no file is uploaded, usable offline.

Revenue

Free basic watermarking; paid unlock for batch processing, PDF export and custom templates at $5-10 one-time or $3/month subscription.

Why now

Identity theft and document leak stories keep surfacing, raising user wariness of 'upload and lose control'. Client-side tech (WASM, Canvas) is now mature enough for full local image processing.