# Image DPI Converter — yeezhan.com
> One-time pay-per-task emergency tool to make your file ready for submission.
> No credits, no balance. One payment unlocks one task result, valid for 24 hours.

Tool domain: https://dpi-image.yeezhan.com
Skill definition: https://dpi-image.yeezhan.com/skill/SKILL.md
API documentation: https://dpi-image.yeezhan.com/api/docs

## What this tool does
Change an image DPI metadata (72→300→600) without touching pixel dimensions — print & visa compliant.

## Typical user problems
- Print systems read DPI metadata, not your pixels. A perfectly good 3000×4000 photo marked "72 DPI" gets rejected for a 300 DPI requirement — and most "converters" quietly resize your image in the process. You need the number changed and the pixels untouched.
- Print shops, publishers and photo-contest systems reject anything not at 300 DPI. Your image is fine pixel-wise — only the metadata says 72. Fix the number, not the image.
- Passport photo printers and professional labs commonly demand 600 DPI. The pixels are already there — the file just needs to declare it.

## Parameters
- target_dpi: number (range 36-2400), required. 目标 DPI. 打印常用 300；像素尺寸不变，仅改元数据
- format: enum, optional. 输出格式

## Pricing
- Watermarked preview: free, no login required
- Final clean output: $0.99 one-time per task
- Require login (email/phone OTP) to complete payment
- Result available for download 24 hours after payment

## Limitations
- Max input 50 MB; pixel dimensions never change
- DPI range 36-2400
- Some social platforms strip DPI metadata on upload (it only matters for print pipelines)