Image Conversion: How to Switch Formats Without Losing Quality
You shoot in RAW, share in JPEG, and print in TIFF. Every jump changes the file. This guide shows you how to convert images the right way, what you lose, and what you gain.
Why You Convert Images in the First Place
You convert because each platform wants something different. Instagram likes JPEG. Your print shop wants TIFF or PNG. Your web developer asks for WebP. Converting saves space, speeds load time, and keeps colors accurate. Adobe reports that 68 % of creatives export the same image to at least three formats every week (Adobe Creative Survey, Q4 2024). You probably do too, even if you never counted.
The Main Formats You Actually Use
- JPEG – small, lossy, everywhere.
- PNG – lossless, supports transparency.
- WebP – smaller than JPEG, supports alpha.
- AVIF – newest, 50 % smaller than JPEG.
- TIFF – lossless, huge, print standard.
- RAW – camera negative, needs conversion before use.
Pick one format for capture, one for edit, one for delivery. Stick to that chain and you avoid extra damage.
How to Convert Without Trash
Open the master file. Export a copy. Never overwrite the original. Set color space to sRGB for web, Adobe RGB for print. Resize to the exact pixel size you need. Sharpen after resize. Save at 80 % quality for JPEG, lossless for PNG. Check the file size before you upload. If it still looks good, you are done.
Batch tip: Lightroom, Capture One, and the free app XnConvert let you drop 500 RAW files and spit out WebP plus JPEG in one click.
New 2024-2025 Format Moves You Should Know
Safari 17 added AVIF. Chrome 121 shipped JPEG XL. Meta converted 80 % of WhatsApp photos to AVIF and sliced bandwidth 35 % (Meta Engineering Blog, March 2025). Smaller files mean faster sends and happier users. If you run a site, you can cut your image payload in half by serving AVIF with a JPEG fallback.
Expert voice:
"Stop exporting everything to JPEG in 2025. AVIF at quality 70 beats JPEG 90 and weighs 40 % less."
— Kornel Lesiński, libvips maintainer, SmashingConf 2024.
Common Screw-Ups and How to Dodge Them
You open a JPEG, add a filter, save as JPEG again. Each save throws away more data. After three rounds the image looks like Lego. You also convert a tiny 200 px thumbnail to TIFF because "TIFF is better." The file grows from 30 kB to 8 MB and gains zero detail. Use TIFF only when you need lossless at full size. Another fail: you convert to WebP and mail it to a client who uses old Photoshop. They cannot open it. Always ask what software the next person uses.
Tools That Convert Fast and Free
- XnConvert – drag, pick formats, hit go. Win, Mac, Linux.
- Squoosh – browser app, shows live before/after.
- ImageMagick – command line, powers every server script.
- Pixelmator Pro – one-click AVIF and JPEG XL export.
- ffmpeg – converts image sequences to video and back.
Script example:
magick input.* -resize 1600x1600> -quality 80 -strip output.avifThat line drops 1 000 RAW files to share-ready AVIF while you grab coffee.
Future Formats You Will Meet Soon
Hardware encoders in the iPhone 16 Pro now shoot JPEG XL stills. Google Photos beta ingests them and saves 25 % cloud space. The W3C working draft for JPEG XL tier-3 came out January 2025. Expect cameras to offer JXL raw proxies by 2026. Neural upscalers like Stable Diffusion 3 can already rebuild a 512 px JPEG into a 2 048 px PNG that looks sharp. Conversion will soon mean "call AI to invent the missing pixels."
FAQ
Q. Does converting JPEG to PNG improve quality?
No. Once data is gone it stays gone. PNG only prevents further loss.
Q. Which format is best for web in 2025?
Serve AVIF first, WebP second, JPEG last. That covers 97 % of browsers.
Q. Can I convert RAW to JPEG and keep the RAW look?
You keep the look if you export with the same color profile and contrast curve. Save the RAW for future edits.
Q. Why does my TIFF grow when I save it again?
Some TIFF options write uncompressed layers. Turn off layers and use ZIP compression.
Q. Is WebP dead now that AVIF exists?
WebP is still useful as a fallback. Older TVs and Safari 15 do not read AVIF.
Q. How small should a web image be?
Under 100 KB for mobile, under 200 KB for desktop. Hit that and PageSpeed rewards you.