Image Converter
Batch-convert JPEG, PNG, and WebP locally with explicit quality, transparency, metadata, and size behaviour.
Processed locally in your browser — these files are not uploaded
Image Converter workspace
1 · Add images
Build your batch.
JPEG, PNG, WebP, and AVIF use the browser’s native decoder where supported. HEIC/HEIF and JPEG XL are also accepted through native decoding when the current browser provides it. No codec bundle is downloaded just for selecting a file.
2 · Output
Choose how to export.
JPEG EXIF orientation is baked into pixels. Source EXIF/XMP/IPTC/GPS metadata is not intentionally copied. Arbitrary ICC/profile preservation and HDR/high-bit-depth preservation are not promised by this browser-native SDR output path.
Checking this browser’s JPEG, PNG, and WebP output support…
3 · Results
Ready to save.
Each output is complete before its download button appears. Browsers can restrict automatic multi-downloads, so Celestia Tools keeps every file explicit.
Choose or drop supported images to begin.
What this converter does
Simple conversions, with the important policies made visible.
Celestia Tools validates the actual image signature, converts one image at a time to keep memory bounded, and only shows a download after a complete output has been produced.
Which formats are supported?
The first verified converter baseline accepts and exports JPEG, PNG, and WebP. Output support is probed in your browser with a tiny real round trip instead of being assumed from the browser name.
What happens to transparency?
PNG and WebP preserve alpha. JPEG does not support transparency, so transparent pixels are flattened onto the matte you choose before encoding.
What happens to EXIF and GPS metadata?
Re-encoding does not intentionally copy source EXIF, XMP, IPTC, GPS, or EXIF orientation. Orientation is baked into the output pixels. This is different from the inspector’s verified lossless JPEG metadata-cleaning path, and this converter does not claim universal removal of every possible vendor-specific metadata structure.
Why are ICC profiles not promised?
The baseline uses the browser’s native canvas encode/decode path. That is useful and fast, but it is not a reference colour-management engine, so arbitrary ICC/profile preservation and HDR correctness are deliberately not promised here.
Why does a batch run one image at a time?
Decoded images can use much more memory than their compressed files. Sequential processing keeps peak memory lower, especially on phones, and releases each decoded image before moving to the next one.
Do my images leave my device?
No. Selected image bytes, filenames, converted outputs, and extracted image data stay in the browser. The page still makes ordinary requests for the site’s own same-origin application assets.