How to compact a Family Tree Maker file
Compacting rebuilds your tree's internal indexes and, with the right box ticked, repairs errors while it goes. Two details decide whether it works: the tree must be closed, and the routine must be repeated until the reported reduction stops falling.
- Applies to
- FTM 2024 · 2019 · 2017 · 2014
- Platform
- Windows & Mac
- Time
- ~30 min
Compacting doesn't delete anything. The file gets smaller because empty space is reclaimed, not because records are removed. Your people, facts, sources, notes and media links come through untouched. It's closer to tidying a filing cabinet than throwing papers away.
What compacting actually does
A Family Tree Maker tree is a database. Every time you add a person, edit a fact, merge a duplicate or delete something, the file grows a little untidier — space gets allocated and abandoned, and the indexes that point to each record drift out of shape. None of this announces itself. It just accumulates.
Compacting does two jobs, and the second is optional:
| Job | What it means | When you need it |
|---|---|---|
| Reclaim space & rebuild indexes | Removes allocated-but-unused space and rewrites the internal record map | Routine maintenance. Always happens. |
| Extended analysis | Inspects the file more deeply, finds errors and repairs them | Any file that has misbehaved. Optional, and slower. |
That second row is the part most people skip, and it's the difference between tidying a file and actually fixing one. It's off by default because it makes the run considerably longer.
When to run it
- Monthly if you're editing regularly — adding people, attaching records, merging.
- Twice a year is plenty if you only dip in occasionally.
- Before any major software update. Going into an update with a tidy file avoids a whole category of problem.
- Before a large sync, since fragmentation is a common reason a sync stalls partway.
- After importing a GEDCOM or merging another file, both of which leave a lot of mess behind.
- Whenever the tree starts feeling sluggish — see speeding up a large tree.
First Back up, even though this is a safe routine
Compacting is well-behaved and rarely causes trouble. It also rewrites your file, and anything that rewrites a file earns a backup first. See how to back up properly.
Step 1 — Close the tree
Most-missed step The routine can't work on an open file
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With Family Tree Maker running, choose to close the tree — but leave the program itself open.
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If you skip this, the tool either won't offer your file or appears to run and achieve nothing. That single detail accounts for most people concluding the feature is broken.
Step 2 — Find the tool
Version-dependent Tools menu, or sometimes File
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Look for Compact File on the menu first. That's where it lives in most versions.
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If it isn't there, check the menu. The publisher's own documentation places it differently across releases, so the menu depends on your version — it isn't missing.
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In the dialog, navigate to your tree file, select it, and click Open.
Step 3 — Tick extended analysis
The setting that matters Turns tidying into repair
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Tick Perform extended analysis. This inspects the file more deeply before compacting, looking for errors and fixing them.
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Expect it to take considerably longer. That's the trade, and it's why the option isn't on by default.
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For routine monthly maintenance you can leave it off. For a file that has crashed, stalled a sync, or behaved oddly, it's the entire reason to be here.
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Click Compact and let it finish without interrupting. On a large tree this can run half an hour or more.
Step 4 — Repeat until it stops shrinking
Nearly everyone stops too early One pass is rarely enough
When it finishes you get a message telling you the file size was reduced by a percentage. Write that number down. Then do the whole thing again.
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Note the reported file size reduction.
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Run the routine again from step 1. The second pass almost always reduces the file further.
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Keep going until the figure reaches 0.00% — or as close as it will get. Some files settle at a small non-zero number and stay there, and that's fine.
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What you're watching for is the percentage ceasing to fall between runs. That's the signal the file has settled.
Still shrinking meaningfully on the fourth or fifth pass? That's a sign of genuine damage rather than ordinary fragmentation. Move on to the file repair guide, which covers what to do when compacting alone isn't enough.
If compacting doesn't fix it
Compacting resolves a lot, but not everything. If the problem persists after several clean passes:
- The damage may be beyond it. Repairing a corrupted file covers restoring a backup, downloading a clean copy from Ancestry, and rebuilding via GEDCOM.
- The cause may still be present. A tree kept in a cloud-sync folder will keep getting damaged no matter how often you compact it.
- It may not be the file at all. If the program won't start, see Family Tree Maker won't open.
Compacting isn't settling the file?
A file that keeps shrinking pass after pass usually has real damage underneath. We'll assess a copy and tell you what's recoverable before you pay anything.
Keeping the file healthy between compacts
- Close the tree properly before shutting down. Forced quits are a leading cause of the damage compacting has to clear.
- Keep the working file on a local drive, never inside Dropbox, OneDrive or iCloud.
- Compact after every import or merge, while you remember why the file grew.
- Put it in the calendar. The whole point is that fragmentation gives no warning — regularity beats reacting.
- Merge duplicates as you go rather than in one enormous session. See merging duplicate people.
Frequently asked questions
How often should I compact my Family Tree Maker file?
Monthly if you edit frequently, and always before a major software update. Twice a year is enough for occasional use. Regularity matters more than frequency — the fragmentation builds gradually and gives no warning before it starts causing problems.
Does compacting delete any of my family tree data?
No. It reclaims space that was allocated but is no longer used, and rebuilds the internal indexes. People, facts, sources, notes and media links are untouched. The file shrinks because empty space is removed, not because anything is discarded.
What does Perform extended analysis actually do?
It examines the file more deeply before compacting, looking for errors and fixing those it finds. That's why it takes considerably longer and isn't on by default. Leave it off for routine maintenance; tick it for any file that's misbehaved.
Why does the Compact File option appear to do nothing?
Nearly always because the tree is still open — the routine works on a closed file. Close the tree first, then open the tool. If the menu item is missing altogether, check both Tools and File, since the publisher documents it in different places for different releases.
My file never reaches 0.00 per cent. Is something wrong?
Not necessarily. Some files settle at a small non-zero figure and stay there. What matters is the percentage ceasing to fall between runs. If it's still dropping meaningfully by the fourth or fifth pass, that points at real damage — see the repair guide.
Should I compact before or after syncing with Ancestry?
Before. A fragmented file is a common reason a sync stalls partway, so compacting first removes that variable. Compacting after a very large sync is also sensible, since a big batch of incoming changes leaves fragmentation behind it.