cm4all

ImpEx is a WordPress plugin that allows you to import and export data from and to your WordPress installation.
The primary goal for ImpEx is to provide a true Open Source WordPress Plugin for importing/exporting your WordPress data (including data from third-party plugins/themes).
This plugin is in an early (but working) stage.
Impex provides :
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WordPress hooks for third-party plugins to expose their own data to ImpEx Import / Export without being dependent on Impex.
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a (semi) streaming architecture for large data exports/imports.
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Definition of configurable import/export profiles defining data providers to use and configuration of these data providers
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<li>A user interface for importing / exporting data via ImpEx WP admin screen</li>
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the ImpEx API is designed to support resumable/cancelable imports and exports.
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ImpEx provides a REST API integrated into WordPress
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ImpEx is explicitly designed for use in managed WordPress instances
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ImpEx development relies heavily on PHP unit testing its feature set to be stable and consistent.
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a <a href="https://ionos-wordpress.github.io/cm4all-wp-impex/impex-cli.html" rel="nofollow ugc">CLI</a> for importing/exporting data via ImpEx REST interface. 
The ImpEx CLI can be used as an alternative to the ImpEx WP admin screen.
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related NPM package <a href="https://www.npmjs.com/package/@cm4all-wp-impex/generator" rel="nofollow ugc">@cm4all-wp-impex/generator</a> enabling transformation of any content to Impex Export format.
Using this package you’re able to convert any content to WordPress and import it using the ImpEx plugin. See the <a href="https://ionos-wordpress.github.io/cm4all-wp-impex/cm4all-wp-impex-generator/static-website-tutorial.html" rel="nofollow ugc">Tutorial</a> 
or <a href="https://www.youtube.com/watch?v=pjG69RmULYo" rel="nofollow ugc">watch the walk-trough at YouTube</a>.
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Your help is welcome !!

cm4all-wp-impex

ImpEx contributes extendable Import / Export functionality to WordPress

chimpify

The Chimpify WordPress plugin allows you to: 
1) Export your WordPress posts, comments, users & media files to <a href="http://chimpify.io/" rel="nofollow ugc">Chimpify</a>. 
2) Import your posts, comments, users & media files from Chimpify to WordPress.
This plugin is currently available in german language only.

Chimpify

Migrate your WordPress data to Chimpify or your Chimpify data to WordPress. Posts, comments, users & media files.

cm4all-wp-impex vs Chimpify