How to Compress TIFF Files on macOS (Preview, Automator & Online)

A single 600 DPI color scan saved as an uncompressed TIFF can run 15-25 MB per page — beautiful for archival, painful for storage and sharing. macOS has the format covered, but the right tool depends on what you actually want: keep TIFF and shrink it losslessly, or convert to a lighter format like JPG or PDF. This guide walks through Preview and Automator (both built into macOS), explains the compression types TIFF supports, and shows where a server-side tool like xconvert fits when you need exact target sizes or batch control.

Quick answer: To shrink a TIFF in macOS without changing format, re-save it with LZW or ZIP/Deflate lossless compression. For a much smaller file, use Preview → File → Export, pick JPEG, click Options, and drag Quality to ~85%. For many files at once, use Automator → Photos → Change Type of Images (add a Copy Finder Items step first to protect originals). For a precise target size — say “under 5 MB” — compress TIFF online lets you set the exact KB/MB you want.

Jump to a section

• TIFF compression types, briefly
• Method 1: shrink a TIFF in Preview
• Method 2: batch with Automator
• Method 3: hit an exact target size online
• Which method should I use?
• How big is a TIFF, really?
• FAQ

TIFF compression types, briefly

TIFF (Tagged Image File Format) was created by Aldus in 1986 and has been maintained by Adobe since it acquired Aldus in 1994; the current TIFF 6.0 specification was finalized in 1992. Unlike JPG, TIFF is a container that can hold image data compressed several different ways — which is why “compress a TIFF” can mean three quite different things.

The practical takeaway: LZW and ZIP are lossless — they reduce size with zero quality change but typically only 20-40% on a color photo. JPEG-in-TIFF is lossy — much smaller, but you lose the archival quality that made you choose TIFF in the first place. If you need a dramatic size cut, converting to JPG or PDF usually beats squeezing the TIFF itself. (Sources: Library of Congress TIFF format description, TIFF on Wikipedia.)

Method 1: shrink a TIFF in Preview

Preview is the image viewer built into every Mac, and it can re-export a TIFF in a lighter format. This is the fastest path for one or two files.

1. Open the file in Preview — double-click the .tiff, or right-click and choose Open With → Preview.
2. Go to File → Export in the menu bar.
3. In the Format pop-up menu, choose your output:
4. JPEG for the smallest file (lossy) — best for photos and single-page scans.
5. TIFF if you must keep the format — Preview will re-save with LZW lossless compression.
6. Hold the Option key while clicking the Format menu to reveal extra formats like JPEG-2000.
7. If you picked JPEG, click the Options button (or expand the Quality row) and drag the Quality slider to about 80-90%. Lower quality means a smaller file; 85% is a good balance where most scans look identical to the source.
8. Choose a destination and click Save.

This Export workflow is the same across macOS Ventura, Sonoma, and Sequoia, per Apple Support. Note that the Quality slider only appears for lossy formats (JPEG, JPEG-2000) — exporting back to TIFF or PNG gives you lossless output with no quality control.

Method 2: batch with Automator

When you have a folder of TIFFs, Automator (also built into macOS, in your Applications folder) converts them all in one pass.

1. Open Automator and choose File → New. Select Quick Action (or Workflow for a one-off run) and click Choose.
2. Protect your originals first. In the Library on the left, find Copy Finder Items, drag it into the workflow, and pick an output folder. This step copies the files so the conversion never overwrites your source TIFFs — Apple recommends it for exactly this reason.
3. In the Library, open the Photos category and drag Change Type of Images into the workflow below the copy step. Automator will offer to add the copy step for you if you skipped it.
4. In the Change Type of Images action, pick your target format from the pull-down — JPEG for the biggest size reduction, or TIFF to stay lossless.
5. To run a one-off Workflow: drag your TIFF files onto the workflow (or add a Get Specified Finder Items action) and click Run at the top right. Saved as a Quick Action, it appears in Finder’s right-click menu so you can convert any selection of files instantly.

The Change Type of Images action is available through macOS Sequoia and supports BMP, JPEG, JPEG-2000, PNG, TIFF, and HEIC output (Apple Automator User Guide). Automator does not expose a JPEG quality slider, so for fine control over size, use Preview or an online tool.

Method 3: hit an exact target size online

Preview and Automator are great for “smaller,” but neither lets you say “make this exactly 5 MB” or apply a specific lossless compressor to a batch. That’s where a dedicated tool helps. With compress TIFF you can:

1. Add your TIFF — drag and drop, or click + Add Files (you can also pull from Google Drive or Dropbox).
2. Open Advanced Options and choose a Compression Type — JPEG (default, lossy), or lossless LZW, Deflate, PackBits, CCITT Fax 4, WebP, JP2K, or ZSTD.
3. Set a target: a percentage of the original, an exact file size in KB or MB, or an image-quality percentage. This is the part desktop tools can’t do — you name the size, the tool hits it.
4. Pick the output file extension (.tiff or .tif — they’re the same format) and click Compress, then download.

Your files upload over an encrypted connection, are processed on xconvert’s servers, and are deleted automatically after a few hours — nothing is shared. In production the median TIFF drops about 84% with these settings; an 8 MB file commonly lands near 1.3 MB.

If the goal is generic image shrinking across formats, the same engine powers the image compressor. And if you’re specifically trying to get a scan under an email cap, the companion guide Compress TIFF for Email walks through the TIFF-to-PDF and TIFF-to-JPG paths step by step.

Which method should I use?

How big is a TIFF, really?

TIFF size is driven far more by resolution and color depth than by the format itself. A letter-size page scanned at 600 DPI in 24-bit color holds roughly 18 million pixels — uncompressed, that’s tens of megabytes per page. Drop to 300 DPI grayscale and the same page is a fraction of the size.

The rough ranking below shows why TIFF feels heavy next to web formats. Exact bytes vary with image content, but the order is consistent: uncompressed TIFF and BMP sit at the top, lossless formats in the middle, lossy JPEG at the bottom.

So if a lossless re-save isn’t shrinking your TIFF enough, the real levers are lowering the resolution, converting color to grayscale where appropriate, or switching to a lossy format. A 600 DPI archival scan rarely needs that resolution for on-screen viewing or email.

FAQ

Is .tif the same as .tiff?

Yes. .tif and .tiff are the same Tagged Image File Format; the only difference is the extension length. .tif survives from older systems (DOS, early Windows) that limited extensions to three characters. Any modern app reads both, and tools like xconvert let you output either.

Does LZW or ZIP compression lose any quality?

No. LZW and ZIP/Deflate are lossless — they rearrange the data to take less space but reconstruct every pixel exactly. The trade-off is modest savings (often 20-40% on photos). For 16-bit TIFFs, ZIP is generally the better choice; LZW can occasionally make a 16-bit file larger. Only JPEG compression inside a TIFF is lossy.

Why is my TIFF still huge after compressing it?

Two usual causes. First, the source is high-resolution color (e.g. 600 DPI, 24-bit) — resolution dominates file size, so lossless compression alone can’t shrink it dramatically. Second, the file may be multi-page; each page adds up. Reduce the resolution, convert to grayscale, or switch to JPG/PDF for a real cut.

Will Preview overwrite my original TIFF?

Only if you save over it. File → Export lets you choose a new filename and location, so your original stays intact. With Automator, add a Copy Finder Items step (as in Method 2) so the batch always works on copies — this is Apple’s recommended way to protect originals during conversion.

Should I keep the original uncompressed TIFF?

For archival, legal, or medical workflows: yes. Those policies typically require the lossless master. Treat any JPG, PDF, or lossy-compressed version as a “working copy” for sharing, and keep the original TIFF in your archive.

Can I batch-compress to an exact file size in macOS?

Not with the built-in tools. Preview’s Quality slider and Automator’s format picker shrink files but don’t target a specific KB/MB. For an exact size across many files, use compress TIFF and set the target file size directly, or the general image compressor for mixed formats.

Sources

Last verified 2026-06-17.

• Apple Support — Convert image file types using Preview on Mac — Preview Export, Format pop-up, Quality slider behavior.
• Apple — Automator User Guide: Quick Action workflows — Change Type of Images action and supported formats.
• Library of Congress — TIFF, Revision 6.0 format description — baseline vs. extension compression, history.
• TIFF (Wikipedia) — Aldus origin, Adobe maintenance, TIFF 6.0 (1992), .tif/.tiff equivalence.