Set exact pixel dimensions or convert to 72 / 150 / 300 DPI for print. Lock aspect ratio. Browser-based, no upload.
PNG, JPG, WebP, BMP — any size, mochi handles it all
After resizing, use the Photo Editor to enhance sharpness and contrast, then Compress to optimize file size for web or email.
Browse All Tools →imagemochi merges three jobs into one tool: a pixel-precise image resizer, a print size calculator, and a DPI metadata converter. Screen mode takes exact width and height in pixels for web, social, and email. Print mode flips it: pick a physical print size (4×6", 5×7", 8×10", A4, A3, custom inches) and a target DPI (72, 150, 300), and the tool figures out the pixels needed — with a visual A4 comparison and a low-pixel warning that hands off to the AI Upscaler when you don't have enough. DPI mode only changes the embedded DPI tag, leaving pixels untouched — perfect for passport portals, photo labs, and Word/InDesign imports that reject files based on metadata. The converter writes real pHYs chunks (PNG) and JFIF density bytes (JPEG), not fake labels. Supports PNG, JPG, WebP, BMP with no file-size limit. Everything runs in your browser; your photos never upload.
pixels = inches × DPI. If you pick a 4×6 inch photo at 300 DPI, the tool needs 1200×1800 pixels to print sharply. The visual preview shows your chosen print size against an A4 reference so you can sanity-check the physical scale at a glance. If your uploaded image has fewer pixels than required, Print mode flashes a low-pixel warning and offers a one-click handoff to the AI Upscaler — it adds the missing pixels, then sends you back to Print mode with all your settings preserved.pHYs chunk for PNG output, JFIF density bytes for JPEG output. Print drivers, Microsoft Word, Adobe InDesign, photo lab uploaders, and passport submission portals will all read this value. WebP doesn't have a standard DPI field, so DPI is skipped if you export to WebP. DPI metadata only changes how the file is interpreted for print — it does not alter pixels, so your image looks identical on screen. To physically resize, change width/height too.pHYs chunk) or modifies 5 bytes (JPEG JFIF density). The visible image is unchanged; only print software reads the new value. If a service rejected your photo as "below 300 DPI", they're checking metadata — embedding 300 DPI here will pass the check. If they rejected it as "low resolution", you need more pixels, which means upscaling — try our AI Upscaler.Curated multi-step recipes that build on this tool — drop an image, get the right output for the destination platform without configuring the steps yourself.