Enterprise Korean document proofreading services compared: what to choose on

In short: Correction quality is not the only thing that decides an enterprise rollout of Korean document proofreading. Whether documents leave your network, whether you can protect internal terminology, whether there is an API to plug into your systems, and whether corrections come with reasons are four criteria that narrow the options sharply.

Four kinds of options

Approach	Typical example	Strengths	Weaknesses
Web spell checker	Naver, Pusan National University checker	Free, instant	Documents leave your network, input limits, no API or a limited one
Human proofreading (copyediting) service	Proofreading agencies	Polishes style and logic too	Per-job cost and turnaround, cannot handle large volumes
General-purpose LLM asked to proofread	Public LLM APIs	Flexible	Unjustified edits, documents leave your network, inconsistent results
Korean proofreading engine	`Bareun`	Grounded in language norms, API, custom dictionary	Paid

What enterprises actually weigh

Criterion	Why it matters	How `Bareun` handles it
Keeping documents in-house	Contracts, HR files, and patient records cannot leave the company	Besides the cloud, an air-gapped setup can be discussed (Adoption guide)
Protecting internal terms	Product names and personal names must not be "fixed" as typos	Custom dictionary changes take effect immediately, with no downtime
Stated grounds	The person in charge has to be able to justify an edit	Returns category, reason, source of the rule, and usage examples together
System integration	It has to run inside groupware, a CMS, or an editor	gRPC, REST, connect-web, streaming correction
Bulk processing	Thousands of documents are run at once	Document-level input, file correction, batch calls
Consistency	Results must not differ from department to department	Everyone shares the model and dictionaries on a single server
Cost predictability	A budget based on usage is needed	Per-plan limits and usage checks
Operational stability	If it stops during work hours, work backs up immediately	Real-time error detection and monitoring, high-availability setup (Enterprise environment)

What happens when you proofread with a general-purpose LLM

LLMs are good at smoothing out sentences, but they change parts you did not ask about and cannot give grounds for their edits. Putting in the same sentence twice can give different answers. Bareun corrects with rules on top of morphological analysis, falls back to an LLM only for eojeols (space-delimited word units) that rules cannot settle, and rejects excessive changes. What was changed and why is recorded as a category, a reason, and the source of the rule (Korean spell checkers compared).

Choosing a deployment form

If documents may leave your network: The cloud API is the fastest route. Call it right away with an issued key (Using the cloud API).
If documents must not leave: Set it up as a self-hosted installation (On-premises adoption guide).
Directly inside authoring tools: Connect to web editors through connect-web and to AI agents through the MCP server (Using the MCP server).

Built with the goal of never stopping

Bareun was developed from the start for enterprise environments where work must not stop. It sits inside work that runs all day, such as document writing, customer support, and search indexing, so "it answers whenever you ask" matters as much as correction quality.

Since the first release in 2023, every error has been detected and monitored in real time.
To date, continuous operation has never been broken.
A high-availability setup is provided by default. The same model runs on several instances, so service continues even if one goes down.
When an error is found, we patch and ship it right away instead of waiting for a regular release.

How to set it up and what to decide when adopting it are covered in Enterprise environment: continuous operation and high availability.

How to protect internal terminology

The most common complaint about enterprise document proofreading is "it changes our product name as if it were a typo." Bareun protects proper nouns and technical terms from correction once you register them in a custom dictionary, and when the dictionary changes, it applies the change immediately without stopping the server. You can specify several dictionaries at the same time, so you can manage glossaries per department and layer them when needed (Custom dictionary API).

Korean spell checkers compared · Spell check APIs compared
Grammarly alternatives for Korean: how they differ from English proofreading tools
Adoption guide for on-premises Korean spell checking
Enterprise environment: continuous operation and high availability

Frequently asked questions

If you cannot send documents outside, must protect internal terminology, or need to connect to groupware or a CMS through an API, an engine like Bareun fits: it corrects on the basis of Korean language norms and provides an API and a custom dictionary. For occasional personal use, a free web checker is enough.

Q. Can't I just proofread with a general-purpose LLM?

It is useful for polishing sentences, but it changes parts you did not ask about, cannot give grounds for why it edited, and its results vary from call to call. For official documents, contracts, and manuals that need rule-based grounds, a proofreading engine based on language norms is the better fit.

Q. How do I stop company product names and technical terms from being changed as typos?

Register them in the custom dictionary and they are protected from correction. Bareun detects dictionary changes in real time and applies them without stopping the server, and you can also keep per-department dictionaries and apply them together.

Q. Can I connect it to internal systems (groupware, CMS)?

You can call it through gRPC, REST, or connect-web, and for long documents, streaming correction can show results progressively. For AI agents, connect through the MCP server.

Q. What happens if the service stops during work hours?

Bareun was developed for environments where work must not stop, and since deployment in 2023 it has detected and monitored every error in real time. Continuous operation has never been broken to date, a high-availability setup is provided by default, and errors are patched and shipped right away when found.

Q. Can I use it without sending documents outside?

The morphological analysis server can be installed in-house. The spell checker uses a lot of resources, so it is provided as a cloud service by default, and an air-gapped setup is arranged through separate consultation.