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  • Introduction to Translation Memory

Introduction to Translation Memory

Transifex has a built-in Translation Memory (TM). TM is a powerful tool that helps with translation quality and consistency. It can even save you money by reducing the amount of repeat and new work a translator has to do.

How Translation Memory works

Without going into too much technical detail, Translation Memory is a database of previously completed translations. Each time a translation is submitted, it's saved to this database. You can also set only the reviewed strings to be added to this database. In the future, if a phrase similar to the original source string appears, the translation is presented to the translator as a suggestion. Let's look at an example.

Say we have one string in our file: "It is sunny and warm in California." When we translate it, the translation is automatically saved to the TM. Then we add another string to the file: "It is sunny and warm in Greece." When the translator goes to work on the new string, they'll see the translation for the first string as a suggestion. While the two strings are not exactly the same, they share a lot of words – both contain the phrase "It is sunny and warm in." By seeing the suggestion, the translator can translate the new string quickly while keeping it consistent with the other translation.

This concept of looking at two phrases which are similar but not exactly the same is known as a fuzzy matching.

In some cases, you may have two phrases which are exactly the same. This is known as a 100% match. Most of the time, if one of the phrases was already translated, you can reuse the translation for the other phrase.

TM in Transifex

Each project in Transifex has its own Translation Memory (TM) instance. It is updated whenever a new translation is submitted. All these translation entries are automatically stored in your project’s TM whether they have been marked as reviewed or simply translated. As an option it is possible to update a TM Instance only when a new translation is reviewed. This option appears in the project settings under the workflow tab. An exception is that automatically machine translated strings are added to your TM only when they are marked as reviewed. The same is true for strings that were machine translated in bulk (by selecting multiple strings within the Editor).

When a new project is created, a TM is automatically generated for this project.

To have a shared TM across multiple projects, you would need to create a TM group, as described here.

Translation Memory suggestions can be exported and imported in a TMX format allowing you to massively update your project’s TMs. Please note that no saved translations are deleted from the TM until the maintainer manually removes it from TM or overwrites the existing TM with an updated version of a TMX file.

This feature is currently available in beta. If this feature hasn't been enabled for your organization yet and you're interested in trying it out, please contact us.

To stop TM from showing in the editor suggestions from languages with the same country code but different locales, you need to disable the relevant option. You may find this option in your project settings, under the workflow tab, in the translation section.


For example, when translating fr_FR, you will see suggestions from the fr locale too, unless you disable this functionality for the specific project. Such suggestions are displayed in the editor as follows:


As long as this setting is enabled, Transifex will show suggestions following the priorities below:

  • similarity %
  • context match
  • language (editor language has priority)
  • last used

So, if we have 2 suggestions with 98%, both with the same context, then the editor language has priority and this is the TM suggestion that will be shown first.


Soon we will release a similar option about fillups. Until then please note that TM fillups don’t use entries across languages that have the same country code but different locales.

How to only allow reviewed translations into the TM

  1. From the Dashboard, click on the project you want to enable TM fill-up for.
  2. Click on Settings.
  3. In the submenu, click on Workflow.
  4. In the Quality Assurance step, enable the Allow only Reviewed translations into the Translation Memory option.

Machine Translations

Machine Translations are not affected by this setting; they always need to be reviewed to enter Translation Memory.

How it works

The "Allow only reviewed translations into the Translation Memory" setting will only take effect for strings that were reviewed after this setting was activated.

This feature is only available on Enterprise plans.

What happens if a language/resource/project is deleted

  • If you delete a language or a resource(s) from your project, all the TM entries will be preserved and available as TM suggestions for future translations.
  • If you delete the whole project, translations for that project will be deleted from the TM, so those TM suggestions will not be available for future translations.

  • If you archive a project, the project’s TM suggestions will still be shared with other projects if the archived project belongs to a TM group.

TM Leverage

The unit of storage in TM is a segment (also referred to as a string), not a sentence. A segment might contain one, a few, or many sentences - depending on the structure of the source file.

TM compares a new segment with the segments that it has in its database. Then, it identifies the similarity match. If the similarity match is 60% or higher, those segments will appear for a translator in the “Suggestions” tab.

Information about the TM leverage before the translation process starts is available in the pop-up window for each resource on a language level:


as well as under “Reports”> "Export TM Leverage":


The detailed statistics about how much TM leverage was used during the translation process can be found in the Translation Activity Report.

Old Translation Versions

When an existing translation is replaced by a newer version and it is not used anymore in a project or projects that belong to the same TM group, then this old version is no longer exposed as a suggestion in Transifex Web Editor.

A translation version is not removed from the TM, when:

1) The corresponding translated source string is removed/deleted from the resource

2) The source text is updated. In this case, the string returns to the untranslated state but the translation of the previous version is still part of the project's TM suggestions