Preview an image next to an adjustable grayscale conversion and export a browser-encoded JPG, PNG or WebP.
01 / CHOOSE IMAGE
Choose or drop one image for browser-only editing.
Maximum 25 MB · 8,000 px per side · 16 million decoded pixels. Supported raster bytes are checked before preview.
02 / EDIT CONTROLS
03 / ORIGINAL & LIVE PREVIEW
Choose an image to preview it.
Edited preview appears after selection.
Dimensions and aspect ratio are preserved for grayscale. A 90° or 270° rotation swaps output width and height.
04 / EXPORT & DOWNLOAD
PNG and WebP retain alpha when supported by the browser. JPEG uses white behind transparent pixels and is lossy. Browser re-encoding can change file size and quality.
Validated images are decoded and edited in your browser. Nothing is uploaded or stored by Nimzoa.
Your text or image stays in your browser.
Adjust the options and review the live result.
Review and save the result locally when available.
Choose one validated JPG, PNG or WebP, adjust grayscale intensity from 0% to 100%, preview the original and output, then export and download.
Original dimensions preserved, live pixel-based grayscale preview, protected transparent PNG/WebP alpha and native browser encoding.
Images are validated and processed only in your browser. No server uploads or external image APIs.
One JPG/JPEG, PNG or WebP at a time, up to 25 MB, 8,000 pixels per side and 16 million decoded pixels. Bytes and dimensions are checked before preview.
At 0% the original RGB channels are retained; at 100% each pixel uses a luminosity-based gray value. Intermediate values blend the two.
Yes. Grayscale changes colors only; width, height and aspect ratio stay the same.
Pixel alpha is preserved on the canvas and when PNG or supported WebP encoding retains it. JPEG uses a white background because it does not support alpha.
Yes. Browser-native encoding produces the selected format when supported. Re-encoding may change file size and lossy output quality.
No. Decoding, preview, processing and export occur locally in browser memory. No server upload or external image API is used.