Machine translation vs. CAT Tools—Collaboration or Competition?

machine translation vs CAT tool

As technology rapidly evolves, professionals across all fields are prompted to modernize their tools and learn new skills to boost productivity. The translation industry is no exception. Gone are the days when translators relied solely on dictionaries and typewriters; today’s experts use CAT tools and MT to streamline tasks. Both computer-assisted translation (CAT) and Machine Translation (MT) are revolutionary software technologies that enhance a translator’s efficiency. 

However, the Machine Translation vs. CAT tools debate remains. Which one holds the edge? When is it best to utilize each tool? And, importantly, are the investments in these tools truly justified?

This article explores the differences between the two technologies, some myths, and how they work together!

Machine Translation vs. CAT Tools: What They Are

Machine Translation is automatic(AI) technology, while CAT is an assistive technology for translation tasks. 

MT is software that can translate text or speech from one language to another without human intervention. Thanks to advancements in artificial intelligence and deep learning, modern MT systems can handle large volumes of text and deliver translations at remarkable speeds. 

At their core, MT systems are built on neural networks that mimic the human brain. Thousands of interconnected nodes work together to solve complex problems. The nodes “learn” language patterns by analyzing vast linguistic databases. They translate by finding the closest match to the new input given to them. The more they are used, the more they improve—producing translations quickly and fluently.

In contrast, CAT tools are software applications designed to aid human translators in their tasks. They typically have functions like:

  • Automatic prompting and suggestions as the translator types
  • Translation memory that stores previously translated segments of text to avoid redundant work
  • Terminology databases to ensure consistency in language use. 

They allow translators to customize the tool to fit their own translation style and work. For instance, if you frequently translate medical documents, the tool lets you add common terms while you type so your translations are consistent.


Machine Translation vs. CAT Tools: Key Differences

Let’s look at some of the differences in detail before exploring the use cases

Nature of Operation

MT operates autonomously and can generate first-draft translations of entire documents and even books within a few minutes. All the translator has to do is upload the document and select the source and target language.

CAT tools don’t operate autonomously. You can think of them as intelligent text-editing software for translators. Translators have to manually type and interact with the software for every sentence.


Machine translation aims to deliver fast translations for vast volumes of text at speed. They can handle internal documents or less critical translations by themselves. For more nuanced work, MT generates the first draft that translators can edit to create the final version.

In contrast, CAT Tools are designed to optimize the workflow of professional translators and to improve efficiency as the translator works. They cannot translate independently.

Learning and Adaptability

Modern MT systems use deep learning and neural networks, enabling them to improve over time based on feedback and vast amounts of data. They learn from the past work of millions of translators. In contrast, CAT tools “learn” by building translation memories from past projects, ensuring consistent translations in subsequent similar texts. They may only have knowledge from the single organization/team or the single translator that uses them.

Cost Implications

In general, MT is much more cost-effective as compared to CAT. Many MT tools offer free translation on the internet. For example, you can translate three documents monthly for free on Systran Translate Pro. You can translate 150 pages for as little as €5 a month. For enterprises, a one-time investment for in-house deployment can save you thousands of dollars over the lifetime of your project.

CAT tools are expensive in their monthly pricing structure. Top tools generally start at €185 / month, reaching nearly €500 / month for enterprise plans. But more than that, they are expensive because they don’t reduce translation time as significantly as MT. A translator can edit an MT-generated first draft in under 30 minutes. If using CAT, the translator must still spend several hours translating the content. 

Machine Translation vs. CAT – some misunderstandings

There are some misunderstandings about both technologies that we would like to clarify.

Myth – MT is replacing translators

Just like CAT, the goal of MT is also to support translators in their work. But the approach is different. Instead of word-by-word help, MT generates the full translation of a page, document, or block of text that the translator only has to edit later on.

Myth – MT cannot specialize in specific domains

Translators can customize CAT tools for their usage with glossaries for special terminology. The same is true for MT too. You can train MT in specific domains like finance, law, or science for different language pairs so the generated first drafts use consistent and accurate term translation from the start. For example, Systran offers trained MT systems in 55+ languages for over ten different domains!

Myth – MT translation lacks the human touch

Quality of MT output depends totally on the neural networks that power it. Domain-specific and localization training ensures machine translation generates drafts that account for cultural nuances and region-specific terminology. Both CAT and MT require humans. Human work is more in CAT as they may have to translate every word, human work is less in MT as the expert only has to post-edit.

How Machine Translation and CAT work together

As technology advances, the lines between the two technologies are blurring rapidly. Many CAT tools offer built-in MT capabilities that use APIs—a software-software communication mechanism—to connect with third-party MT services. For example, top CAT tools like MemoQ and SmartCAT integrate with Systran translate Server to provide MT capabilities within their tools.

Today, companies have many choices. You can use:

  • MT solution as in-house deployment for internal use or in your applications.
  • Machine Translation as a fully managed service in your business process automation or client interface.
  • Machine Translation only to quickly translate a document and do light touch editing in Word or any other text editing software.
  • Machine Translation to create first-draft translations and CAT tools for post-editing.
  • CAT tools with built-in MT capabilities to work within a single system.

It is no longer a question of competition but collaboration. Pick and choose the right combination of tools to best suit your requirements!

Alexandre Translation Technology Specialist
4 Min Read
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