Project Duplicator API

Create a new project from an existing one: its settings, its members and its teams. No content is copied — no files, strings, translations, TM or glossary entries, whatever the flags say: they are named after settings so that none of them reads as a copy of content.

Contract version 1. Call it through the Crowdin API with a token that has the application.proxy scope:

• Enterprise: https://{organization}.api.crowdin.com/api/v2/applications/create-project-app/api/{path}
• crowdin.com: https://api.crowdin.com/api/v2/applications/create-project-app/api/{path}

Parameters go in the JSON body or in the query; Crowdin merges the query into the body, so numbers and booleans are accepted as text too. Crowdin wraps every answer into data and keeps its HTTP status, so every body says ok and status itself.

How a copy goes

1. GET /duplication-preview shows what would be copied, who would be added, invited or skipped and why, and what is never copied. It writes nothing, and it is also the export of who has access to the source.
2. POST /duplication with an idempotencyKey answers once the project is created, with the status of the copy. Members, teams and resources are copied after the answer.
3. GET /duplication-status every pollAfterMs (5000 ms), or with wait, until the status is one of succeeded, partial, failed, needsAttention.

Statuses: queued, running, succeeded, partial, failed, needsAttention, interrupted. interrupted is not final: the app is restarting, and the copy goes on once it is back, so keep polling. partial means the project exists but something did not make it: show it as created with remarks, never as a success. needsAttention means Crowdin did not confirm the creation and the app will not guess: candidates lists the projects it may have made, and a POST with the same key and adoptProjectId goes on with one of them. Phases, in progress.phase only: creating, settings, members, teams, resources, done.

Endpoints

{
  "ok": true,
  "status": "ok",
  "platform": "enterprise",
  "source": {
    "id": 123,
    "name": "Mobile App",
    "identifier": "mobile-app",
    "type": "file-based",
    "sourceLanguageId": "en",
    "sourceLanguageName": "English",
    "targetLanguages": [
      {
        "id": "uk",
        "name": "Ukrainian"
      }
    ],
    "hasAdvancedWorkflow": true,
    "workflowSteps": [
      {
        "id": 313,
        "type": "Translate",
        "title": "Translation"
      }
    ],
    "settingsValues": {
      "qaCheckIsActive": true
    }
  },
  "target": {
    "groupId": 45,
    "groupPath": "Workspace/Mobile",
    "workflowTemplateId": 7,
    "suggestedWorkflowTemplateId": null,
    "workflowTemplateRequired": true,
    "stepMapping": [
      {
        "sourceStepId": 313,
        "targetStepId": 998,
        "matchedBy": "positional"
      }
    ],
    "mappingMethod": "positional"
  },
  "settings": {
    "groups": [
      {
        "key": "qa",
        "title": "Quality assurance",
        "default": true,
        "resource": false,
        "fields": [
          "qaCheckIsActive",
          "qaCheckCategories"
        ],
        "values": {
          "qaCheckIsActive": true
        },
        "requires": [],
        "blockedBy": null
      },
      {
        "key": "placeholders",
        "title": "Placeholders",
        "default": true,
        "resource": true,
        "fields": [],
        "values": {
          "switchedOff": [
            {
              "id": "printfSpecifier",
              "label": "C-style format specifiers"
            }
          ],
          "customPlaceholders": [
            {
              "name": "Ticket reference",
              "customPlaceholderId": 12,
              "type": "high",
              "index": 0,
              "isBlocking": true,
              "formats": [
                "docx"
              ]
            }
          ]
        },
        "requires": [],
        "blockedBy": null
      }
    ]
  },
  "members": {
    "copied": true,
    "total": 42,
    "byOutcome": {
      "willAdd": 33,
      "willInvite": 0,
      "willSkip": 9
    },
    "estimatedInvitations": 0,
    "list": [
      {
        "id": 11,
        "login": "ann",
        "name": "Ann",
        "roles": [
          "translator"
        ],
        "languages": [
          "uk"
        ],
        "allLanguages": false
      }
    ],
    "skipped": [
      {
        "id": 12,
        "login": "eve",
        "name": "Eve",
        "code": "MEMBER_BLOCKED_SKIPPED",
        "message": "This member is blocked in the source project, so they were not added."
      }
    ],
    "detailsTruncated": false
  },
  "teams": {
    "copied": true,
    "supported": true,
    "total": 3,
    "willAdd": 3,
    "list": [
      {
        "id": 4,
        "name": "Reviewers"
      }
    ],
    "skipped": []
  },
  "resources": {
    "labels": 12,
    "exporterSettings": 3,
    "taskSettingsTemplates": 1,
    "reportSettingsTemplates": null,
    "resourceBindings": 2,
    "placeholders": 2
  },
  "warnings": [],
  "notCopied": [
    {
      "key": "content.files",
      "title": "Files and folders",
      "reason": "outOfScope",
      "code": null
    }
  ],
  "unknownFields": [],
  "limits": {
    "maxMembers": 5000,
    "maxTeams": 500,
    "memberBatchSize": 25,
    "maxWaitSeconds": 60,
    "invitationConfirmationThreshold": 50
  },
  "contract": {
    "version": 1,
    "duplicationUrl": "/duplication",
    "statusUrl": "/duplication-status",
    "idempotencyKeyRequired": true,
    "pollAfterMs": 5000
  }
}

{
  "idempotencyKey": "7f1c2a0e-3c1b-4d0e-9a57-5a4c0f1d2e3b",
  "sourceProjectId": 123,
  "name": "Mobile App (copy)",
  "targetGroupId": 45,
  "workflowTemplateId": 7,
  "copy": {
    "targetLanguages": true,
    "qa": true,
    "placeholders": true,
    "sourceStringSettings": true,
    "importSettings": true,
    "exportSettings": true,
    "translationSettings": true,
    "tmSettings": true,
    "aiPrompts": true,
    "notifications": true,
    "languageMapping": true,
    "inContext": false,
    "labels": false,
    "exporterSettings": false,
    "taskSettingsTemplates": false,
    "reportSettingsTemplates": false,
    "resourceBindings": false,
    "members": true,
    "teams": true
  },
  "memberOptions": {
    "onUnmappedSteps": "skipRole",
    "acknowledgeInvitations": false
  },
  "wait": 0
}

{
  "ok": true,
  "status": "running",
  "duplicationId": "dup_01J8ZB6Q4W2N5V7X9Y0A1B2C3D",
  "idempotencyKey": "7f1c2a0e-3c1b-4d0e-9a57-5a4c0f1d2e3b",
  "project": {
    "id": 987,
    "name": "Mobile App (copy)",
    "identifier": null,
    "url": "https://acme.crowdin.com/u/projects/987/files"
  },
  "candidates": [],
  "startedAt": "2026-09-23T10:00:00.000Z",
  "finishedAt": null,
  "progress": {
    "phase": "members",
    "done": 12,
    "total": 45
  },
  "report": {
    "settings": {
      "requested": [
        "targetLanguages",
        "qa",
        "aiPrompts"
      ],
      "copied": [
        "targetLanguages",
        "qa"
      ],
      "failed": [
        {
          "key": "aiPrompts",
          "code": "SETTING_REJECTED",
          "message": "qaCheckActionAiPromptId: <the wording of Crowdin>",
          "details": {
            "fields": [
              "qaCheckActionAiPromptId"
            ],
            "retryable": true
          }
        }
      ]
    },
    "members": {
      "total": 42,
      "counts": {
        "added": 33,
        "updated": 0,
        "invited": 0,
        "skipped": 8,
        "failed": 1
      },
      "added": [
        {
          "id": 11,
          "login": "ann",
          "roles": [
            "translator"
          ],
          "languages": [
            "uk"
          ],
          "allLanguages": false
        }
      ],
      "skipped": [],
      "failed": [],
      "detailsTruncated": false
    },
    "teams": {
      "supported": true,
      "total": 3,
      "counts": {
        "added": 2,
        "skipped": 1,
        "failed": 0
      },
      "added": [
        {
          "id": 4,
          "name": "Reviewers"
        }
      ],
      "skipped": [
        {
          "id": 9,
          "name": "FR squad",
          "code": "TEAM_PERMISSIONS_NOT_PORTABLE",
          "message": "The access of this team cannot be rebuilt in the new project, so the team was not added."
        }
      ],
      "failed": []
    },
    "resources": {
      "labels": {
        "total": 12,
        "copied": 12,
        "failed": 0,
        "skipped": 0,
        "items": []
      },
      "placeholders": {
        "total": 2,
        "copied": 1,
        "failed": 0,
        "skipped": 1,
        "items": [
          {
            "name": "Ticket reference",
            "outcome": "skipped",
            "code": "CUSTOM_PLACEHOLDER_FORMAT_UNAVAILABLE",
            "message": "This custom placeholder is limited to file formats the new project cannot use, such as one of an app the project has no access to, so it was not assigned. Give the project access to that format, then assign the placeholder by hand."
          }
        ]
      }
    },
    "notCopied": [
      {
        "key": "content.files",
        "title": "Files and folders",
        "reason": "outOfScope",
        "code": null
      },
      {
        "key": "webhooks",
        "title": "Webhooks",
        "reason": "outOfScope",
        "code": "WEBHOOKS_NOT_COPIED"
      }
    ],
    "warnings": [],
    "unknownFields": []
  },
  "errors": [],
  "statusUrl": "/duplication-status",
  "pollAfterMs": 5000,
  "replayed": false
}

{
  "ok": true,
  "status": "partial",
  "duplicationId": "dup_01J8ZB6Q4W2N5V7X9Y0A1B2C3D",
  "idempotencyKey": "7f1c2a0e-3c1b-4d0e-9a57-5a4c0f1d2e3b",
  "project": {
    "id": 987,
    "name": "Mobile App (copy)",
    "identifier": null,
    "url": "https://acme.crowdin.com/u/projects/987/files"
  },
  "candidates": [],
  "startedAt": "2026-09-23T10:00:00.000Z",
  "finishedAt": "2026-09-23T10:01:12.000Z",
  "progress": {
    "phase": "done",
    "done": 45,
    "total": 45
  },
  "report": {
    "settings": {
      "requested": [
        "targetLanguages",
        "qa",
        "aiPrompts"
      ],
      "copied": [
        "targetLanguages",
        "qa"
      ],
      "failed": [
        {
          "key": "aiPrompts",
          "code": "SETTING_REJECTED",
          "message": "qaCheckActionAiPromptId: <the wording of Crowdin>",
          "details": {
            "fields": [
              "qaCheckActionAiPromptId"
            ],
            "retryable": true
          }
        }
      ]
    },
    "members": {
      "total": 42,
      "counts": {
        "added": 33,
        "updated": 0,
        "invited": 0,
        "skipped": 8,
        "failed": 1
      },
      "added": [
        {
          "id": 11,
          "login": "ann",
          "roles": [
            "translator"
          ],
          "languages": [
            "uk"
          ],
          "allLanguages": false
        }
      ],
      "skipped": [],
      "failed": [],
      "detailsTruncated": false
    },
    "teams": {
      "supported": true,
      "total": 3,
      "counts": {
        "added": 2,
        "skipped": 1,
        "failed": 0
      },
      "added": [
        {
          "id": 4,
          "name": "Reviewers"
        }
      ],
      "skipped": [
        {
          "id": 9,
          "name": "FR squad",
          "code": "TEAM_PERMISSIONS_NOT_PORTABLE",
          "message": "The access of this team cannot be rebuilt in the new project, so the team was not added."
        }
      ],
      "failed": []
    },
    "resources": {
      "labels": {
        "total": 12,
        "copied": 12,
        "failed": 0,
        "skipped": 0,
        "items": []
      },
      "placeholders": {
        "total": 2,
        "copied": 1,
        "failed": 0,
        "skipped": 1,
        "items": [
          {
            "name": "Ticket reference",
            "outcome": "skipped",
            "code": "CUSTOM_PLACEHOLDER_FORMAT_UNAVAILABLE",
            "message": "This custom placeholder is limited to file formats the new project cannot use, such as one of an app the project has no access to, so it was not assigned. Give the project access to that format, then assign the placeholder by hand."
          }
        ]
      }
    },
    "notCopied": [
      {
        "key": "content.files",
        "title": "Files and folders",
        "reason": "outOfScope",
        "code": null
      },
      {
        "key": "webhooks",
        "title": "Webhooks",
        "reason": "outOfScope",
        "code": "WEBHOOKS_NOT_COPIED"
      }
    ],
    "warnings": [],
    "unknownFields": []
  },
  "errors": [],
  "statusUrl": "/duplication-status",
  "pollAfterMs": 5000
}

Errors

The same envelope on all three; error.httpStatus is the HTTP status of the answer, and error.duplicationId names the duplication a refused copy ended in.

{
  "ok": false,
  "status": "error",
  "error": {
    "code": "SOURCE_FORBIDDEN",
    "message": "You need manager access to the source project to copy its settings and members.",
    "httpStatus": 403,
    "details": {
      "projectId": 123
    },
    "duplicationId": null
  }
}

What is copied

Always, whatever the flags: sourceLanguageId, type, description, visibility (crowdin.com), fields (Enterprise). The flags:

A setting Crowdin refuses on creation is left out and the project is created without it, reported in report.settings.failed with the wording of Crowdin and a partial status. Resource bindings attach the TMs, glossaries and style guides of the source, its default TM and glossary among them, to the copy as additional ones; the copy keeps the TM and the glossary Crowdin creates with it as its defaults, so its translations never go into a TM of the source. Their entries are not copied. TM priorities stay those of the source on crowdin.com, where the highest one is the number of TMs of the project owner. Enterprise accepts no priority above the number of TMs of the project, so there priorities the copy cannot have become their rank, in the same order. The preview counts what each resource flag would copy under resources, one key per flag; a count is null when the app does not copy that group here (settings.groups[].blockedBy says why) or could not count it.

placeholders, on by default, copies the placeholders the project recognizes, which Crowdin keeps apart from the settings of the project: every built-in placeholder switched off in the source is switched off in the copy, one JSON-Patch each, and on Enterprise the custom placeholders of the organization assigned to the source are assigned to the copy with the same type, index, isBlocking and formats, in the order of their index. The custom placeholders themselves belong to the organization and are shared, so none is created or changed. One limited to formats the copy cannot use is skipped with CUSTOM_PLACEHOLDER_FORMAT_UNAVAILABLE, and one deleted meanwhile with CUSTOM_PLACEHOLDER_DELETED; neither makes the copy partial. Placeholder unification, normalizePlaceholder, is a setting of sourceStringSettings and importSettings. In the preview, settings.groups[] of placeholders lists the built-in placeholders switched off in the source under values.switchedOff and, on Enterprise, its custom placeholders under values.customPlaceholders, null where Crowdin did not list them. Where Crowdin has no placeholder routes (Crowdin Enterprise of the Connector edition answers 404), the group is reported in notCopied with endpointUnavailable, which is also its blockedBy in the preview, it is not counted, and the copy is not partial for it. A caller that leaves the flag out gets placeholders copied.

Resources are copied last, after the teams and the members. Labels go by title, without the strings they are assigned to; system labels are left alone. Task settings templates go with their languages as they are and keep as assignees only the people and teams the copy has; a template without languages, and every template when the target languages are not copied, is skipped with LANGUAGE_NOT_IN_TARGET. The report counts every resource flag under report.resources (total, copied, failed, skipped), and items names what failed or left something behind. A resource list Crowdin refuses to give makes the copy partial, never stops it.

Members

Members are added with the roles they have in the source, rebuilt for the languages and workflow steps of the copy. memberOptions.onUnmappedSteps decides what happens to access to a step the copy has no match for: skipRole (default) leaves that access out, strict refuses the copy before anything is created, allContent widens it to all steps and names every widened grant in the report. The owner of the source, blocked members, pending invitations (crowdin.com), organization admins and group managers without a project role of their own, and technical accounts are never added, each with its code; an admin or a group manager with a role of their own gets that role alone. On Enterprise a person who has not accepted the invitation to the organization yet is copied like any member. On Enterprise the teams of the source are added after the members, since Crowdin skips whoever a team already makes a manager of the copy with their roles of their own, and the people of a team are not added one by one.

Access can be limited to Translate and Proofread steps only, so only those steps of the source and of the workflow template are compared; pre-translation, vendor, application and custom code steps neither count nor shift the positions. They map by position when both have them in the same order of types, by position within a type when only the order or the titles differ, and not at all otherwise: target.mappingMethod is positional, byType or none, and target.stepMapping pairs each such step of the source with its step in the copy, null when it has none. A member or a team left without a role because its languages are not target languages of the copy is skipped with LANGUAGE_NOT_IN_TARGET under every policy. When the preview counted on those languages and the creation of the copy lost them, the member or the team fails with the same code instead.

With copy.members or copy.teams off, the preview keeps members and teams in their shape with copied: false and total: null: nobody was read, so there is nothing to count. teams.supported is then null on Enterprise, since whether Crowdin lists the teams of the source is only known once they are asked for.

On Enterprise the task reviewers of translationSettings are set once the members and the teams are in, and only those who are managers of the copy then: Crowdin accepts no one else. The others are listed in notCopied under taskReviewerIds with details.reason notManagers and their details.userIds; a refusal of Crowdin is a failed setting of a partial copy.

Never copied

notCopied[].reason is one of outOfScope, notImplemented, platformUnsupported, crowdinOnly, endpointUnavailable.

Codes

HTTP errors

Two of them came after version 1 of the contract froze its catalog:

• VALIDATION_FAILED 400: A parameter the app cannot read: an empty name, an idempotencyKey over 128 characters, a malformed identifier, an unknown key in copy or memberOptions, a value of the wrong type, a wait outside its range, a status request with neither duplicationId nor idempotencyKey, or a body that is not JSON. error.details.field names the parameter.
• APP_RESTARTING 503: A POST /duplication that comes while the app is shutting down for a restart, before the copy has started. Nothing was created: send the same request with the same idempotencyKey again in a minute.

In the report

Per setting, member, team and warning, inside a copy that as a whole went through.

Three of them came after version 1 of the contract froze its catalog:

• UPSTREAM_RESULT_UNKNOWN: A failed member or team whose write Crowdin answered with a timeout or a 5xx, when the members or the teams of the copy, read back right after, do not list it or cannot be read, or whose write a stopped run left pending when the copy cannot be read. A timeout or a 502 of the proxy does not stop the write in Crowdin, so it may still go through. The app does not send it again; on crowdin.com the invitation may have gone out, so a member other than a manager or a developer, who join at once, has invited "unknown". One the copy lists is reported as added or invited.
• CUSTOM_PLACEHOLDER_FORMAT_UNAVAILABLE: A custom placeholder of the source limited to file formats Crowdin does not let the copy use, such as the format of a custom file format app available to selected projects only. It is skipped rather than assigned to every format, and the copy is not partial for it.
• CUSTOM_PLACEHOLDER_DELETED: A custom placeholder deleted from the organization between the preview of the copy and its assignment: skipped.

Errors that never reach the app

Limits

• At most 5000 members and 500 teams in the source (SOURCE_TOO_LARGE), limits of the app itself.
• Members are added 25 per request to Crowdin, the ones with the manager, developer or language coordinator role one per request: Crowdin checks the managers limit of the plan for a whole request, so one person who needs a new seat would get everyone in it refused.
• wait up to 60 seconds.

Limitations

1. Who can call it: on Enterprise the owner and the admins of the organization, on crowdin.com only the account the app is installed under. Project managers duplicate projects in the window of the app. A 403 or a 404 from Crowdin for anyone else means exactly this.
2. Crowdin does not check the permission of an api module on its proxy, only whether the caller has full access to the apps of the organization: whoever can call one of the three endpoints can call all of them.
3. The app acts with the permissions of whoever installed it, never with those of the caller: there is no token per user. A preview and a duplication check the caller in the app as well, for a call that comes past the proxy: on Enterprise an admin of the organization, on crowdin.com a manager of the source project. The status of a run is found by its id, 80 random bits. Enterprise has an app authentication of the type crowdin_app_with_code, which acts as the caller, and crowdin.com has none; this app does not use it and acts with the token of the installer on both.
4. Crowdin waits 15 minutes for an answer and has no callbacks, so the API is asynchronous: a POST answers once the project is created, and wait is capped at 60 seconds.
5. The paths of api modules have no dynamic segments: every id is a parameter.
6. On crowdin.com a copy always gets the default workflow, as project creation there accepts no workflow, so access the source limits to some workflow steps is lost in the copy: those members get all the steps of their languages. This cannot be detected through the API: for a source with a workflow of its own Crowdin already reports such access as all the steps of the language, so the preview and the report do not name these members. STEP_RESTRICTIONS_NOT_PORTABLE appears only for the access Crowdin does report as limited to some steps.
7. On crowdin.com every member added gets an email against the daily limit of invitations of the organization: 1000 a day outside a trial, 2 to 100 a day in a trial depending on its age, and a separate limit of 50 for invitations with the manager role (numbers of Crowdin that may change). A manager or a developer joins the copy at once; a translator, a proofreader or a language coordinator is invited and joins once they accept. The rest of the limit cannot be read; above 50 estimated invitations the POST needs memberOptions.acknowledgeInvitations, and once Crowdin refuses one the remaining ones are reported as INVITE_LIMIT_REACHED.
8. On crowdin.com a member is a manager, a developer or holds language roles, never two of these: a member the source lists as a manager or a developer with language roles as well is added with the manager or the developer role alone. A manager has every language with the role; for a developer the preview and the report name the language roles left out in notCopyableRoles.
9. Rolling the app back removes its api modules from every organization by itself; bringing them back takes another Apply of the update by an admin.
10. On Enterprise the people who reach the source through a team are read from the members of its teams, with the team:read scope of the same update. Where it cannot be read no team is copied, and the teams are reported as TEAM_PERMISSIONS_NOT_PORTABLE.
11. Crowdin marks no technical account in the members of a project: one is skipped when Crowdin refuses to add it, with TECHNICAL_DETECTION_UNAVAILABLE.
12. On Enterprise the custom placeholders of the copy are named in the preview and the report by their description, or their definition, from the list of the organization, which the custom-placeholder:read scope of the same update reads. Until an admin applies it, or where Crowdin refuses that list, they are named by their numbers; what is copied stays the same.
13. Every built-in placeholder switched off in the copy is one request to Crowdin, and one entry in the activity of the new project. crowdin.com no longer shows the custom placeholders some projects were given before it kept them to Enterprise, so those are not copied.
14. Webhooks of the source are not copied, and neither are its pending invitations on crowdin.com (MEMBER_PENDING_SKIPPED): no second email is sent to anyone. On Enterprise a person invited to the organization who has not accepted yet already has the project access they were given, and the members listing of the project has nothing that marks them, so the copy gives them the same access.