The Unison Insider’s Guide
Everything we know about Unison in one document: what it costs, its grades, getting a refund, getting help and what else to look at. Read it here, or keep a copy.
Unison
The Insider’s Guide
Open-source two-way file synchronizer for Unix, macOS and Windows
Every plan, grade, refund rule and rival among file storage and sync services, read from Unison’s own pages.
Made by Unison open-source project · checked Nov 13, 2026 · toolgpa.com
Contents
- 01WelcomeWhat it is, who it suits, its grades and the ten things to know first
- 02What it costsEvery plan, the free plan, ways to pay less and how prices have moved
- 03What it doesIts main features, where it runs, what it works with and who makes it
- 04Where it standsIts grades against its category, and whether to keep it or make your own
- 05The alternativesThe tools it is most often weighed against, side by side
- 06Quick answersThe questions people ask about it, each answered in a line or two
- 07About ToolGPAWho made this guide, what else is on the site, and how to cite it
ToolGPA put this guide together from Unison’s own pages, its app-store listings and our grades. Every fact in it is on Unison’s page too, where it is kept up to date. Checked Nov 13, 2026.
Part 01 · Overview
Welcome
What it is, who it suits, its grades and the ten things to know first
2.6
GPA, above 62 of the 91 other file storage and sync services we grade
Unison is a free file-synchronization tool that keeps two copies of a folder tree up to date when both are edited separately. It runs between hosts, usually over ssh, and flags conflicting changes instead of overwriting them. It is distributed as source code under the GNU General Public License, version 3.
To get you started, here are 8 things to know about Unison, taken from its own pages and our grades.
A command-line program released as source, with pre-built binaries from packaging systems.
- 1
Best for two-way file sync, free and open source
Unison is a free open-source program that keeps two copies of a folder in step, on Mac, Windows and Linux, over ssh or TCP.
- 2
It is free
Unison has no paid plan at all.
- 3
It runs on 3 platforms
macOS, Windows and Linux.
- 4
Two-way synchronization
Changes made on either replica are propagated to the other, and updates that do not conflict are applied automatically.
- 5
Conflict detection
When both sides changed the same file, Unison shows the conflict instead of silently picking a winner.
- 6
Cross-platform pairs
It can synchronize a Windows laptop with a Unix server, for example, over ssh or directly over TCP.
- 7
A 2.6 GPA, above 62 of 91
That is against the other file storage and sync services we grade, on value, the free plan, features, ease of use and platforms.
- 8
Keep it
Unison is free, so making your own would save you nothing.
Unison at a glance
- Pricing
- Free
- Free plan
- It is free
- Free trial
- None stated
- Runs on
- macOS, Windows, Linux
- Made by
- Unison open-source project
- Category
- File Storage & Sync
- Our grade
- 2.6 GPA, good
The report card
Best for two-way file sync, free and open source
Unison is a free open-source program that keeps two copies of a folder in step, on Mac, Windows and Linux, over ssh or TCP. It flags conflicts instead of picking a winner, but you get source code, the maintainers say few people work on it, and it is run from a terminal.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | A | Free under the GPL-3.0 licence, with no paid editions. Anyone can download and run it. |
| Free plan and trial | A | The whole program is free with no limits, and you only need the two places to sync. |
| Features | C | Two-way sync, conflict detection, rsync-style transfers and repeat mode. It does that one job fully, and it is a smaller job: no cloud services or mobile. |
| Ease of use | D | A command-line program released as source, with pre-built binaries from packaging systems. Help comes from a wiki and mailing lists. |
| Platforms and integrations | C | A program for computers alone: Mac, Windows and Linux. No phone, web or cloud integrations are listed. |
An A is worth 4 points, a B 3, a C 2, a D 1 and an F nothing. The GPA is the average of the five.
Who Unison is for
- Fits if you are happy in a terminal and want conflict-aware sync between two machines
- Works for people syncing a laptop with a Unix server over ssh
Who it is not for
- Skip it if you want a point-and-click app, as it is run from the command line
- Watch out: the project releases source, and pre-built binaries come from other sources
- Tight if you need help: the README says not to ask in GitHub issues
- Watch out: the maintainers say very few people work on it, so fixes are slow
- Not for you if you want cloud storage sync, as it is two-folder sync
Good to know
Good for
- Keeping a laptop and a home or remote server in step over ssh
- People comfortable with command-line tools and config files
- Syncing without a cloud account or any subscription
Worth knowing
- The project releases source code; pre-built binaries come from packaging systems or CI builds.
- The README says not to ask for help in GitHub issues; questions go to the wiki and mailing lists.
- The maintainers say very few people work on it, so bug and feature handling is slow.
- The old project website is archival; development and issues are on GitHub.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
Free
No paid plan at all
Unison is free to use.
The whole program is free with no limits, and you only need the two places to sync.
Free
$0
Full source code under the GNU General Public License, version 3; there are no paid editions.
Read from github.com on Nov 13, 2026.
Part 03 · Features
What it does
Its main features, where it runs, what it works with and who makes it
3
Places it runs: macOS, Windows and Linux
Open-source two-way file synchronizer for Unix, macOS and Windows. Here is what it does, as its own site describes it, and what it covers: open source, works offline, file sync.
Two-way sync, conflict detection, rsync-style transfers and repeat mode.
- Two-way synchronization
- Changes made on either replica are propagated to the other, and updates that do not conflict are applied automatically.
- Conflict detection
- When both sides changed the same file, Unison shows the conflict instead of silently picking a winner.
- Cross-platform pairs
- It can synchronize a Windows laptop with a Unix server, for example, over ssh or directly over TCP.
- Efficient transfers
- Small edits to large files use a compression protocol similar to rsync's, which suits slow links.
- Repeat mode
- With a filesystem monitor, repeat mode propagates changes soon after they happen.
- No special privileges
- It is a user-level program: no kernel changes, superuser rights or FUSE are needed on either host.
Where it runs
- macOS
- Windows
- Linux
What it works with
Its own pages name no integrations.
Unison is made by Unison open-source project.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
62/91
Other file storage and sync services it is graded above
Unison's GPA of 2.6 is higher than 62 of the 91 other file storage and sync services we grade, and level with 10.
It stands best on free plan and trial (A, above 86 of 91) and worst on ease of use (D, above 0).
Unison has no paid plan.
On features, ease of use and platforms it scores 1.7 out of 4. Nothing scores higher for less, though at least one tool matches that score at a lower price.
Each grade against the category
Every bar is all 92 file storage and sync services we grade, cut by the letter each got. Unison’s own letter is outlined.
- AValue for moneyAbove 74 of 91
- AFree plan and trialAbove 86 of 91
- CFeaturesAbove 2 of 91
- DEase of useAbove 0 of 91
- CPlatforms and integrationsAbove 1 of 91
Price against what you get
Each dot is one of 66 file storage and sync services. Further left costs less; higher up scores better on features, ease of use and platforms. Unison is the marked dot.
What paid plans start at, a month (each step along is roughly double) →
Keep it, or make your own?
Whether this is something you could build for yourself with an AI app builder, and what you would give up.
Keep it
Unison is free, so making your own would save you nothing.
And it is not the kind of software a weekend replaces. It is one of the better ones too: its GPA of 2.6 is higher than 62 of the 91 other file storage and sync services we grade.
What you could not
- Files kept in step across devices without losing one.
- Apps for macOS, Windows and Linux that stay in step with each other.
What this rests on. Unison’s listing: what it does, where it runs, what it plugs into and what it costs. It is a judgement about the kind of software this is. We have not built a replacement for it, and making your own means looking after it too. How we decide, and every tool’s verdict.
Part 05 · Alternatives
The alternatives
The tools it is most often weighed against, side by side
Syncthing, Rclone, FreeFileSync and Syncovery
The 4 tools Unison is most often weighed against, with where each one differs from it.
- 2.6GPA
Syncthing
Free
- 2.8GPA
Rclone
Free
Command-line tool for syncing and mounting cloud storage.
- Only Rclone lists an Android app.
- Rclone is end-to-end encrypted, according to its own site.
- Rclone also covers file management.
- 3.0GPA
FreeFileSync
Free plan · from €20/yr
Open-source folder comparison and sync for desktops.
- FreeFileSync also covers file management.
- 2.4GPA
Syncovery
Free trial · from $39.90 one-time
One-time-license file sync and backup for desktops and NAS.
- Unison has a free plan. Syncovery does not, though it has a free trial.
- Unison is open source, according to its own site.
- Syncovery can be bought with a one-time purchase.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
12
Questions, each answered in a line or two
The short version of everything above, for when you only need the answer. Each one is told in full in its part of the guide.
Is Unison free?
Yes. Unison is free to use.
How much does Unison cost?
Unison lists one plan. Free: $0.
What platforms does Unison work on?
Unison is available on macOS, Windows and Linux.
Does Unison have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. Unison is listed for macOS, Windows and Linux.
Does Unison have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. Unison is listed for macOS, Windows and Linux.
Is Unison open source?
Yes. Unison is open source, according to its own site.
Does Unison work offline?
Yes, according to its own site. What works without a connection differs by plan and platform, so check the vendor's page for the detail.
Who makes Unison?
Unison is made by Unison open-source project.
What are the alternatives to Unison?
The closest alternatives to Unison in our directory are Syncthing, Rclone, FreeFileSync and Syncovery.
How does Unison compare with other file storage and sync services?
Unison's GPA of 2.6 is higher than 62 of the 91 other file storage and sync services we grade, and level with 10.
Is Unison good value for money?
ToolGPA grades Unison A for value for money. Unison has no paid plan.
Could I make my own version of Unison?
Unison is free, so making your own would save you nothing. And it is not the kind of software a weekend replaces.
Where this guide comes from
The prices, plans, platforms and features were read from Unison’s own pages on Nov 13, 2026, and the grades were given on Nov 13, 2026. Graded from this listing, whose facts were read from Unison's own pages on 13 November 2026. Not based on using the product, and shorter than our full reviews.
Every tool we list gets five grades, A to F, each with its reason, and a GPA that averages them. How each is decided is at toolgpa.com/grades. This guide is ToolGPA’s own work; it is not made, paid for or approved by Unison open-source project. Prices change, so check cis.upenn.edu before you buy.
Part 07 · About
About ToolGPA
Who made this guide, what else is on the site, and how to cite it
7,721
Tools graded, in 95 categories
ToolGPA grades software the way a school report grades a pupil: five subjects, a letter for each with the reason written beside it, and a GPA that averages them. Prices, plans and platforms are read from each maker’s own pages and dated, so you always know how fresh a figure is.
Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Every tool on the site has a guide like this one, free to download and pass on. It all lives at toolgpa.com.
7,721
tools graded
95
categories
739
price changes on record
579
apps priced in 12 countries
What else is on toolgpa.com
- Unison, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/unison
- How grades are givenThe rules behind every letter and every GPAtoolgpa.com/grades
- Value chartsWhat each tool costs against what it scores, for every categorytoolgpa.com/charts
- CompareAny two tools side by side, plan by plantoolgpa.com/compare
- Price changesEvery price rise and cut on record, each with its sourcetoolgpa.com/price-changes
- Prices by countryWhat apps cost on the App Store in 12 countriestoolgpa.com/prices-by-country
- Pay lessEvery public discount: yearly billing, students, nonprofitstoolgpa.com/save
- Keep or makeWhich tools are worth paying for, and which you could build yourselftoolgpa.com/keep-or-make
Scan for the live page
Prices and grades as they are today
Quoting this guide?
Please name ToolGPA and link to the live page, so readers can check the figures for themselves:
ToolGPA, "Unison: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/unison
Know someone choosing between file storage and sync services?
Send them this guide: toolgpa.com/tools/unison/guide
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See our other guides
The best-graded file storage and sync services after Unison, each with an Insider's Guide of its own.
- File Storage & Sync Insider's GuideEvery one of the 92 file storage and sync services we grade, compared
- Google Drive Insider's GuideCloud storage tied to Google Docs, Gmail and Photos3.6 GPA
- Filen Insider's GuideEnd-to-end encrypted cloud storage from Germany with open source apps3.4 GPA
- Microsoft OneDrive Insider's GuideMicrosoft's cloud storage, bundled with Microsoft 365 plans3.4 GPA
Choosing software? Every tool graded, every price dated.
Compare tools at toolgpa.com ›Everything in this guide is ToolGPA’s own summary of what Unison’s pages, its app-store listings and public reviews said on the dates shown. Grades are our judgement under the rules at toolgpa.com/grades. Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Unison is a trademark of its owner, and this guide is not made, paid for or approved by Unison open-source project. Prices and plans change: check cis.upenn.edu before you buy.