Lighten

IPHONE GUIDE

How to reduce an iPhone photo to 1 MB or less

If an upload form asks for a photo no larger than 1 MB, set that limit in Lighten and check the actual output. Keep the original pixel dimensions when you only need a smaller file. The finished file determines whether the limit is met.

Steps in Lighten

  1. Check the upload requirements

    Find out whether 1 MB applies to each photo or to all files combined. Also check the accepted formats and any exact width and height. Lighten applies its size limit to each file.

  2. Choose a photo

    Open Lighten and select a photo from Photos or Files. Lighten prepares a separate result and leaves the original unchanged.

  3. Set a 1 MB limit

    Enable the file-size limit in the output requirements, choose MB and enter 1. Keep the original format and dimensions unless the upload requires a change. Choose a smaller compression preference when needed.

  4. Set dimensions only when required

    A maximum dimension can use the longest-edge setting, which scales proportionally. For an exact width and height, enter both values, adjust the framing yourself and explicitly confirm it before processing. The initial framing is only a preview.

  5. Check the actual result

    Read the output byte count and pixel dimensions. Compare the original and result, especially text, faces and other important details. The estimate shown before processing is not the finished file size.

  6. Save the copy and return to the upload

    Save the checked result to Files or Photos, then select that new copy on the original upload page. Meeting the file-size limit does not guarantee acceptance; the destination may have additional format or content requirements.

How many bytes are in 1 MB?

Lighten uses decimal units: 1 KB = 1,000 bytes and 1 MB = 1,000,000 bytes. A 1 MB limit means the actual output must not exceed 1,000,000 bytes.

Use the exact byte count rather than a rounded MB label. If the destination explicitly requires less than 1 MB, set a slightly lower limit and check the result. Websites may define MB differently, so use the requirements shown on the destination.

File size and pixel dimensions are different

Compression can reduce file size while keeping the same pixel dimensions. A longest-edge limit scales down proportionally and does not force a crop.

An exact width and height lock the target aspect ratio. You choose what stays in the frame and confirm the crop; the photo is not stretched to that ratio. A file-size requirement alone is not a reason to remove part of your photo.

What if the photo cannot reach 1 MB?

Check which requirements you are allowed to change. Try a smaller compression preference, or lower the longest edge if there are no fixed pixel dimensions. Check the new output for lost detail.

Exact pixel dimensions and confirmed framing remain fixed. Lighten will not silently shrink those dimensions or change the crop to meet the byte limit. If no candidate fits, change the requirements or choose a suitable source; a failed result is not marked ready.

Format changes and Live Photos

Choose JPEG if the upload requires JPG. Otherwise, start with the original format. Converting a transparent image to JPEG gives it a solid background. Format and device support can also affect HDR and other preserved information; review the app’s notice before accepting changes.

A Live Photo contains still and motion resources. Lighten keeps its original format and dimensions, and the motion resources also take space. A low limit may not be achievable; an ordinary photo’s compression result is not a promise for every Live Photo.

Will the original be replaced?

No. Lighten creates a new result on your iPhone without replacing or automatically deleting the source. Single-file processing is available within the daily free allowance, with inspection before saving or sharing.

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