U8x8 Fonts 〈Simple〉

Define your custom font array directly in your firmware structure:

The is a highly optimized, monochrome text display system designed specifically for resource-constrained microcontrollers like Arduino, ESP8266, and ESP32. As a subset of the widely popular U8g2 graphics library, U8x8 strips away complex graphical rendering pipelines to deliver lightning-fast text performance and an incredibly low memory footprint. What are U8x8 Fonts?

: A classic project, an NTP clock using an ESP8266 or ESP32, can display the time in large, easily readable numbers using U8x8 fonts. The library's efficiency allows the microcontroller to focus on network tasks rather than complex graphics rendering.

: Includes the entire character set, including standard ASCII, extended symbols, and sometimes accented characters (approx. 256 characters).

When people search for "u8x8 fonts," they often quickly pivot to "u8x8 proportional fonts." There is a common misconception here. u8x8 fonts

Perhaps the most compelling feature of U8x8 fonts is their minimal memory footprint. While the full U8g2 graphics library often requires a frame buffer that can consume over 1,000 bytes of RAM for a modest 128×64 display, the U8x8 library operates with no frame buffer at all. This fundamental architectural choice means that U8x8 can run on microcontroller boards that would struggle with the graphics-heavy U8g2 library.

Whether you are an Arduino hobbyist, a firmware engineer, or a retro-computing enthusiast, understanding u8x8 fonts is essential for getting text onto your screen without crashing your microcontroller.

The font only includes ASCII 32-127. Extended characters require specific fonts with "extended" or "cyrillic" in the name. Fix: Use u8x8_font_8x8_cyrillic or u8x8_font_cp437 for IBM Code Page 437 symbols.

Here is a minimal but complete example showing how to use U8x8 fonts on an SSD1306 display using I2C connection: Define your custom font array directly in your

“Why?” she asked.

: Contains standard ASCII characters (usually codes 32–127).

U8x8 is one-half of the U8g2 graphics library developed by Oliver Kraus. The library, which supports over 70 different display controllers and more than 700 fonts, provides two distinct APIs to serve different use cases: U8g2 and U8x8. The U8x8 component was designed with a specific philosophy: it is a that works exclusively with fonts that fit into an 8×8 pixel grid. Unlike its counterpart, the full U8g2 library, U8x8 writes characters directly to the display without requiring any graphics buffer in the microcontroller‘s RAM. This direct-to-display approach is the key to its remarkable memory efficiency.

One of the most powerful aspects of the U8x8 system is its built-in UTF-8 support. By default, U8x8 uses ISO/IEC 8859 (Latin-1) encoding, but enabling UTF-8 mode is straightforward. In your setup function, you add a single line: : A classic project, an NTP clock using

The draw2x2String or draw2x2Glyph functions scale the 8x8 source glyph into a 16x16 pixel box.

The U8x8 text-only library—part of Oliver Kraus’s ubiquitous U8g2 graphics framework—is the secret weapon for developers using resource-constrained microcontrollers like the Arduino Uno, ESP8266, or STM32. When your project demands text readouts on OLED or LCD screens but lacks the RAM to handle heavy graphical buffers, U8x8 is the ultimate solution.

One of the more powerful features of the U8x8 library is the ability to access and modify individual glyph data on the fly. The function u8x8_get_glyph_data() allows you to copy an 8×8 character tile into a buffer, modify it, and then redraw it. A typical Arduino implementation might look like: