CK3 to EU5 converter

Is there a CK3 to EU5 converter?

Not a finished one, as of 9 Nov 2026. Paradox has not released a converter from Crusader Kings 3 to Europa Universalis V. The converter people mean is CK3toEU5, a community project of the Paradox Game Converters team on GitHub. That team also makes the CK3 to EU4 converter.

CK3toEU5 is still in development. Its only tagged releases are 0.0 builds from 14 Mar 2026. The main branch now reads a CK3 save, but the mod it writes for EU5 is still a placeholder. It does not yet place your realm on the EU5 map.

An unofficial fork goes further. Its author posted a preview build on the EU5 Steam forum on 23 Sep 2026. It turns independent CK3 realms into EU5 countries, but it skips wars, alliances, heirs, and mods. If you want a finished campaign carried forward now, CK3 to EU4 is the proven path. What is Crusader Kings 3 covers the game itself.

Status and where to get it

The official community source is the GitHub repository ParadoxGameConverters/CK3toEU5. It is MIT licensed and written in C++. The last code change on main before 9 Nov 2026 was a province mapping update on 8 Nov 2026. Earlier 2026 work added the save parser, character linking, dynasties, and faith and culture mapping files.

The readme in the data folder and the converter frontend both point to one Paradox forum thread: CK3 to EU5 Converter Thread. The release checklist in the repository says each release gets a new post there and an updated first post.

The repository has a NO_AI policy, added on 5 Apr 2026. It refuses code, documentation, pull requests, and issues written by generative AI. The author of the Steam fork says the fork is separate because the official project does not accept AI-assisted work.

Builds come from the GitHub releases page, which the frontend's update checker also points to. The release workflow uploads a Windows build to the release tagged latest on each push to main. Until the output step is finished, those builds still write the placeholder mod.

• Sources
• CK3 FAQ

How to use it, step by step

The steps below are the ones the CK3toEU5 readme and frontend describe. The CK3 to EU4 converter uses the same frontend. 1. Download the Windows build from the GitHub releases page and run ConverterFrontend.exe. 2. Point it at your CK3 install folder and your CK3 documents folder. 3. Point it at your EU5 install folder and your EU5 mod folder. 4. Pick your save, a .ck3 file from the CK3 save games folder.

5. Give the mod a name, or leave the default. 6. Click Convert. 7. Start Europa Universalis V and pick the playset that holds the new mod. The frontend is set to overwrite that playset. The result is an EU5 mod, not an EU5 save. You start a new EU5 game with the mod on.

Save rules for EU5 are not written down yet. The code checks that the file starts with the SAV header that CK3 saves carry. It melts a binary save into text with the Rakaly library. The CK3 to EU4 converter credits the same Rakaly melter, and its FAQ says yes, an ironman save can be converted. No CK3toEU5 document says the same yet.

Make the save at the moment you want to hand over. The converter reads the realm as it stands in that file. A split after a succession is what it sees.

What converts and what does not

The official main branch reads most of the save but writes almost nothing. Two community efforts go further: the fork described on the EU5 Steam forum, and pull request 34 to the official repository. Both describe a playable EU5 start that leaves many systems at EU5 defaults, with nearly the same lists.

In those previews, each independent CK3 realm becomes an EU5 country with its land, capital, name, and rank. Vassals at duke tier or higher become subjects of their liege. Land outside any converted realm keeps EU5's own countries. Everyone starts at peace.

Early testing found rough edges. A tester on 26 Sep 2026 reported custom cultures shown as vanilla cultures on some rulers, large realms split into separate nations, capitals moved, and cities, towns, and most buildings missing. The pull request says play past the first day was not tested.

GitHub, CK3toEU5 pull request 34, opened 24 Sep 2026 (read 2026-11-09)

Preparing your CK3 save

Only independent realms become countries in the fork. If you want one strong EU5 country, end the CK3 campaign as one independent realm. A partition that splits your titles before the save shows up as separate realms. Succession crash course explains how Confederate Partition makes a new same-rank title, and Survive a partition shows how to keep the capital duchy together.

Faith converts county by county, through a mapping from CK3 faiths to EU5 religions. A vanilla faith has a line in that file. A faith you founded yourself is not in that list, and the fork post says custom faiths do not convert reliably. If the EU5 religion matters to you, a realm on a vanilla faith is the safer handover. Faith and conversion covers the realm priest and founding a faith.

Culture works the same way. The official project maps CK3 cultures through culture group and language files, and the fork keeps EU5 cultures where they fit. A tester saw custom cultures come out as vanilla cultures on some rulers. Read Culture traditions and Hybrid culture before you diverge or hybridize late in a campaign you mean to convert.

Your dynasty does not travel far. The fork converts the ruler, not heirs, spouses, or the wider dynasty. Renown and legacies have no listed EU5 mapping in either build. Dynasty and renown is still where the CK3 game is won, but plan for the house to stay behind.

• The first 100 years
• Feudal, clan, and tribal

CK3 to EU4, the stable path

The CK3 to EU4 converter is the finished tool from the same team. PCGamesN covered it on 1 Oct 2020, a month after CK3 launched. It is a standalone program that reads the end state of your save: rulers, heirs, and borders. The readme has you copy the output into your EU4 mod folder and select it in the launcher.

The current release is 0.17 Quanzhen. Its title lists CK3 1.18 to 1.19 and EU4 1.37. The converter checks the save version against that range and stops with a version mismatch error if the save is newer. The hub's data patch is 1.20.1.2, so check the release thread for a newer build before you convert a 1.20 save. Patch 1.19 covers the last version that release names.

The EU4 converter offers choices the EU5 project does not have yet. You can start at the EU4 date of 1444 or at your CK3 save date. You also choose which empire takes the EU4 Holy Roman Empire mechanics: the Holy Roman Empire, the Byzantine Empire, Rome, or none. The FAQ says ironman saves work, and mods work unless they change cultures, religions, or flags.

Paradox did once sell a converter. PCGamesN notes that the CK2 to EU4 converter came first as a pre-order bonus and later as DLC. No such product exists for CK3 to EU4 or CK3 to EU5.

• Holy Roman Empire
• Byzantine Empire

Timing: CK3 ends in 1453, EU5 starts in 1337

A default CK3 campaign ends on 1 Jan 1453. You can set the End Date game rule to No End Date when you start a new game, but that choice turns off achievements. Europa Universalis V starts in 1337 and covers about 500 years. It released on 4 Nov 2025.

The two games overlap for 116 years, from 1337 to 1453. A CK3 save from the default end date is later than the EU5 start. The fork maps the realms in your save onto the EU5 map, but no source says what start date its mod uses. The EU4 converter lets you pick 1444 or your save date. The EU5 project has no such option yet.

If you want a CK3 campaign to feed EU5, you do not have to play to 1453. A save from the 1330s is closest to EU5's own start year. Bookmarks start in 867, 1066, or 1178, and The first 100 years covers the first century.

Expansions and patches the converter supports

No CK3toEU5 build lists supported CK3 versions yet. The official readme leaves those lines blank. The fork's pull request says it was tested on a fresh vanilla CK3 1.19 save from the 867 start, loaded in EU5 1.3.11. Patch 1.19 is that version.

By God Alone came out on 30 Sep 2026 with the free 1.20.0 Crozier update, after that test. It is part of Chapter V. No source yet says how the fork handles a 1.20 save or the Papacy and clerical content.

Silk and Silver is announced for 17 Nov 2026, with merchant and republic governments. It is not out, so no converter build can support it yet. How those governments map to EU5 is unknown.

Hegemony is the title tier above empire, added by All Under Heaven on 28 Oct 2025. The official CK3toEU5 code already reads hegemony titles from the save, but nothing is written for them yet. The EU4 converter gives China's hegemony the EU4 Celestial Empire and relinks it to EU4 tags. For EU5 there is no stated mapping. See the Chinese hegemony realm for the CK3 side.

• Patch 1.19The version the fork was tested on
• By God Alone30 Sep 2026, with patch 1.20.0
• Chapter VThe expansion pass By God Alone opens
• Silk and SilverAnnounced for 17 Nov 2026
• HegemonyThe title tier above empire