The Undertale Font: What It Is and How to Match It

What font Undertale actually uses

Undertale, released in 2015 by Toby Fox, was built with custom pixel lettering rather than a licensed off-the-shelf typeface. The game's credits do not list a type foundry for its text, and no standalone version of the dialogue font has been published or sold by the developer.

Fans have traced the letterforms from the game's sprite sheets and circulated unofficial recreations under names such as "Determination Mono" or "Determination Sans." These are fan-made approximations based on observation of the game's graphics, not files pulled from the original game, and they carry no endorsement from Toby Fox. At least two custom letter sets appear in the game: a monospaced bitmap face used for dialogue boxes and menus, and a separate, chunkier style reserved for the "UNDERTALE" logo and a handful of UI headers.

Two characters break from the custom lettering entirely, as a joke built into the game: the skeleton Sans speaks in the standard system font Comic Sans, and his brother Papyrus speaks in the Papyrus typeface. Both are ordinary commercial or system fonts rather than pixel art, chosen specifically because the font names match the characters' names.

Visual traits of the dialogue lettering

• Monospaced: every character occupies the same fixed-width box, so columns of text line up evenly.
• Built on a small pixel grid, giving letters blocky, stair-stepped edges rather than smooth curves.
• Mostly right angles and straight strokes, with curves reduced to the minimum needed for legibility.
• Designed to read cleanly at low resolution without anti-aliasing or smoothing.
• Even, mechanical letter spacing consistent with terminal and early computer display fonts.

These traits describe the main bitmap font used for most dialogue. Sans and Papyrus's lines, covered above, use unrelated commercial fonts instead.

Visual traits of the logo lettering

The "UNDERTALE" title treatment is bolder and wider than the dialogue font, with slightly rounded corners on otherwise angular strokes. It is not monospaced and is used sparingly, mainly on the title screen and packaging, rather than for running text. The developer has not named a reference typeface for this logo, so any resemblance to a known commercial face is visual only, not confirmed.

Closest legal alternatives for the dialogue look

No commercial font is confirmed to match the original bitmap face exactly, but several free, legally distributable typefaces capture the same terminal-pixel character:

• Press Start 2P — designed by CodeMan38, hosted on Google Fonts under the SIL Open Font License. A blocky, arcade-style monospace face that reads close to classic pixel game text.
• VT323 — designed by Peter Hull, also on Google Fonts under the OFL. Modeled on old DEC terminal displays, giving a thinner but still monospaced pixel feel.
• Silkscreen — designed by Jason Kottke, available through Google Fonts under the OFL. A compact bitmap face with simple, squared letterforms.

For a plainer monospace without the pixel-art look, standard system fonts such as Consolas or Courier New will match the fixed-width rhythm without the retro texture. For the Sans or Papyrus look specifically, use the system fonts Comic Sans MS and Papyrus directly, since those are the actual fonts the game uses for those characters.

Matching the look in a design tool

To approximate the effect in a layout or mockup tool:

1. Choose one of the pixel monospace fonts above rather than a generic sans-serif.
2. Set the point size to a round number, such as 16px or 32px, so the pixel grid scales cleanly instead of blurring.
3. Turn off font smoothing or anti-aliasing where the tool allows it, or export the text as a flattened bitmap at the target size.
4. Leave letter spacing at the font's default, since these faces are already monospaced and extra tracking breaks the grid alignment.
5. Use a limited palette, commonly white or pale text on a dark or black text-box background, with a thin single-color border if recreating a dialogue box.

Licensing and trademark limits

The name "UNDERTALE," its logo, and its characters are protected by copyright and trademark rights held by Toby Fox. Using the game's name or logo on merchandise, apps, or marketing can create a trademark problem even if the font itself is unrelated, because the issue is the brand association, not the lettering.

Fan-made recreations of the bitmap font circulate under varying terms set by whoever built them, and those terms are not uniform and can change or disappear over time. Read the license text that comes with any such file before using it in a published project, since some permit personal use only, and check the current terms directly from wherever the file is hosted rather than assuming they match what is described here.

The Google Fonts alternatives named above are released under the SIL Open Font License, which permits free use in personal and commercial projects, including modification and embedding. That license covers the font file only. It does not grant any right to use the Undertale name, logo, or character likenesses alongside it.