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How to Handle Batch compression: 2026 Step-by-Step

To handle Batch compression, confirm the input/format and output requirements, then follow the steps and verify the result.

Updated 2026-11-01About 3 minLocal test
Quick answer

To handle Batch compression, confirm the input/format and output requirements, then follow the steps and verify the result. Set one target (size/quality/format), spot-check a few, then run the batch.

Why it matters

Defining the output first avoids finishing before discovering the format/size/quality is wrong.

Do not use one quality for both text and photos.

Step by step

  1. Back up the original; never overwrite the only copy.
  2. Confirm the target platform's format, dimensions and size limit.
  3. Cap the longest side first, then quality; change one variable at a time.
  4. Compare size and sharpness after compressing, and step back one setting if needed.
  5. Keep the original until the output is confirmed.

Common mistakes

  • Chasing the smallest file and blurring text/edges.
  • Converting transparent PNG to JPEG, turning transparency white or black.
  • Recompressing the same file and accumulating loss.
  • Overwriting the original, so a bad result cannot be undone.

Checklist

  • Original backed up.
  • Output format/dimensions/size meet the platform.
  • Text is readable and transparency is correct.
  • Verified in the real page/email/upload field.
  • Original kept until confirmed.

Key facts

  • Do not use one quality for both text and photos.
  • Spot-check 2-3 outputs after a batch to catch global mistakes.

FAQ

How do I handle Batch compression?

To handle Batch compression, confirm the input/format and output requirements, then follow the steps and verify the result. Set one target (size/quality/format), spot-check a few, then run the batch.

How long does it take?

Usually 1-3 minutes; for intermittent issues, run 30 seconds and retest elsewhere.

Is data uploaded?

Runs locally and does not upload video/audio; extensions may still read the page.

Source: ImageMagick