An editor that produces clean, valid HTML saves you years of debt. A poor editor generates bloated markup, uses deprecated tags, embeds inline styles, or leaves trailing spaces. When you need to migrate later—to a new platform, a new editor, or a new framework—clean HTML ports cleanly. Messy HTML requires scrubbing.
`? Semantic tags? Is it minified or readable? Can you customize it?
API surface
You'll need to read the editor's value, set it from code, and respond to change events. Good editors expose these as simple methods. Avoid editors where you have to dig into the DOM or rely on undocumented properties.
Paste handling
Word documents bring a ton of garbage markup. Does the editor strip it automatically? Can you customize cleanup? This is where most user frustration lives.
Licensing and support
Will the vendor still support it in 5 years? Do you own the code or license it? Can you customize it? Is there source code access if you need to debug?
Mobile and accessibility
Does it work on tablets? Can screen readers navigate it? Keyboard-only users need full access to toolbar features.
Red flags
- Editor hasn't been updated in 2+ years
- No sample HTML output or API docs
- Requires specific framework versions (locks you in)
- Expensive per-user licensing (hard to scale)
- No way to customize keyboard shortcuts or toolbar
- Documentation is sparse or forum-only
Try before you commit
Get a trial license (most vendors offer 30 days), build a small test form, and copy some real user data into it. Paste Word docs. Upload images. Check the HTML in the database. If the output doesn't look right at this stage, it won't improve later.
What changes on each .NET stack
The checklist above applies everywhere, but each framework adds its own questions. These are the ones that catch teams out. (Still on NicEdit? See replacing NicEdit.)
ASP.NET Core (MVC and Razor Pages)
Check that the editor posts its HTML as an ordinary form field, so model binding just works, and that image upload comes with a server-side endpoint for ASP.NET Core rather than only a JavaScript front end. ASP.NET Core has no built-in request validation, so nothing stops script tags arriving in that HTML: sanitize it on the server before you save it (see security below).
ASP.NET MVC (.NET Framework)
MVC 5 rejects posted HTML by default. You will need [AllowHtml] on the model property that receives the editor's value, and you should still sanitize it yourself, because turning validation off for that field removes the only built-in check.
Blazor
Ask whether the component supports two-way binding (@bind-Value) so the editor behaves like any other Blazor input, and whether it works in Blazor Server, WebAssembly, or both. Most editors are JavaScript underneath, so check how much JS interop you have to write yourself and how it behaves when a component re-renders.
ASP.NET Web Forms
You want a server control that you drop on the page and read like a TextBox. Web Forms request validation also blocks HTML posts, so the page (or the control) must handle that, and the control should survive postbacks without losing content.
Plain JavaScript and HTML
If you are not tied to a framework, a framework-agnostic JavaScript editor is the most portable choice: one script, one element, and an API to read and write the HTML. Check its bundle size and whether it works without a build step.
Security: always sanitize on the server
A rich text editor sends HTML to your server, and anyone can post HTML to your server without using the editor at all. Treat the value as untrusted: run it through an allow-list HTML sanitizer before saving or displaying it, so only the tags and attributes you expect survive. Client-side filtering inside the editor is a convenience for honest users, never a security boundary.
A scorecard for your shortlist
Score each candidate 1–5 on these points after a one-day trial with real content.
| Criterion | How to test it |
|---|
| HTML output | Format a page, save it, and read the HTML in your database. |
| Paste from Word | Paste a real Word document with lists, tables and images. |
| Framework fit | Bind it to a model or component the way you bind any other input. |
| Uploads | Upload an image and check where it lands on your server. |
| Accessibility | Use the toolbar with the keyboard only. |
| Licensing | Price it for your real number of developers, domains and years. |
| Longevity | Check release history and how long the product has been supported. |
Questions
What is the best rich text editor for ASP.NET Core?
The one that produces clean HTML, binds to your models like any other field, ships a server-side upload endpoint for ASP.NET Core, and has a licence that fits your team. Shortlist two or three and score them with real content using the table above.
Is there a free rich text editor for Blazor?
There are free and open-source options as well as commercial ones. Whichever you pick, check that it supports two-way binding and the Blazor hosting model you use, Server or WebAssembly.
How do I stop users posting dangerous HTML?
Sanitize the HTML on the server with an allow-list sanitizer before saving or displaying it. Never rely on filtering inside the editor.
Why does ASP.NET MVC reject my editor's HTML?
MVC request validation blocks posted HTML. Add [AllowHtml] to the model property that receives the editor's value, and sanitize that value yourself.
Should I choose a perpetual licence or a subscription?
A perpetual licence is usually cheaper over the several years an editor stays in an application; a subscription spreads cost and bundles updates. Price both for your real team size and timeframe.
Learn more: Rich Text Editor for JavaScript, ASP.NET Core and Blazor, Cute Editor for ASP.NET and Rich Text Editor examples show clean HTML output and extensive APIs.