5 Common Image Conversion Mistakes and How to Avoid Them
After processing millions of image conversions, we see the same mistakes repeatedly. Here are the five most common ones and how to avoid them.
Mistake 1: Choosing the Wrong Format
The most frequent error is converting everything to PNG “because it’s high quality.” PNG is lossless, yes — but that means enormous file sizes for photographs. A 12MP photo saved as PNG can be 15–25MB. The same photo as JPEG at quality 90 is under 2MB with no visible difference.
The fix: Use JPEG or WebP for photos. Use PNG for screenshots, logos, and graphics with text. Read our format comparison guide for detailed recommendations.
Mistake 2: Ignoring Quality Settings
Converting at quality 100 doesn’t mean “best possible image” — it means “largest possible file.” For JPEG and WebP, quality 100 produces files 3–5x larger than quality 85 with no perceptible visual improvement.
The fix: Use quality 80–90 for general use. Or better, use smart quality mode which automatically finds the optimal level using perceptual analysis (SSIM comparison).
Mistake 3: Not Stripping EXIF Data
Every photo from a phone or digital camera contains EXIF metadata: camera model, settings, and often GPS coordinates. When you share photos online, this metadata travels with them. That selfie you posted? It might contain your exact home address.
The fix: Strip EXIF data before sharing photos publicly. Keep it when sending to clients or for archival. Read our EXIF guide for details.
Mistake 4: Upscaling Beyond Reason
Enlarging a 200x200 thumbnail to 2000x2000 doesn’t create detail — it creates blur. Image upscaling interpolates new pixels, but it can’t invent information that wasn’t captured.
The fix: KoalaPic limits upscaling to 4x the original dimensions with Lanczos interpolation, which produces the sharpest possible result. But the best approach is to start with a high-resolution source. If you need a large image, find a larger original.
Mistake 5: Ignoring Color Profiles
A photo that looks perfect on your Mac might look washed out or oversaturated on a Windows PC. This is often a color profile mismatch — the image uses an Adobe RGB or Display P3 profile that the viewing application interprets as sRGB.
The fix: For web images, convert to sRGB before publishing. sRGB is the universal standard for screens and browsers. Read our color profiles guide for the full explanation.
Bonus: Re-Compressing Already Compressed Images
Converting a JPEG to another JPEG (or JPEG → WebP → JPEG) compounds compression artifacts. Each lossy conversion degrades quality. This is called generation loss.
The fix: Always convert from the highest-quality source available. If you have the original RAW or PNG, start there. Never chain lossy conversions.
Next Steps
- Try smart quality compression to find the optimal settings
- Read about lossy vs lossless compression
- Learn about format selection for your use case