How do I write Guðrún in plain ASCII, d or dh?

Use d, which gives Gudrun. That's the standard fallback, and it's what Icelandic passports print in their machine-readable line. Watch out for the usual accent-stripping trick: ð has no decomposition, so NFKD plus dropping non-ASCII deletes it and leaves Gurun. A transliteration library such as Python's unidecode maps it to d properly.

What's the difference between Ð and Þ in Icelandic?

Ð is the voiced th of English this, and Þ (byte 222) is the voiceless th of thin. They also split by position: þ starts words, as in Þór and það, while ð only turns up inside or at the end of a word, as in Guðrún and góð. Both are separate letters in Icelandic, not variants of d or t.

ASCII 208

Uppercase ethBox T-junction pointing up, double vertical

ASCII 208 is Ð on Windows and ╨ in old DOS.

Ð (Capital Eth) is byte 208 in Windows-1252, Unicode U+00D0. Icelandic and Faroese use it for the th sound, and since no Icelandic word starts with ð, the capital mostly appears in all-caps text like GARÐUR. Its twin is the trouble. Croatian and Vietnamese Đ (U+0110, D with stroke) looks identical as a capital but is a different letter, and Windows-1250 stores Đ on this same byte. So Croatian text read as Windows-1252 keeps a convincing Ð in Đakovo, while lowercase đ turns into the Icelandic ð. UTF-8 stores Ð as C3 90, and 90 is unassigned in Windows-1252. The HTML entity is Ð.

╨ (Double Up, Single Horizontal) is byte 208 in code page 437, the original IBM PC character set, and maps to Unicode U+2568. It sits on a single-line bottom edge where a double column line ║ (186) comes up into ─ (196), the reverse of the mix at ╧ (207). Code page 850 used this byte for the Icelandic ð, so a file written in 850 and opened as 437 shows the tee wherever ð should be: garður becomes gar╨ur. In UTF-8 it's E2 95 A8, and the HTML entity is &boxhU;.

Latin LetterBox Drawing

Technical Details

Code Example

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#include <stdio.h>

int main(void) {
    /* On Windows (code page 1252) byte 208 is Ð.
       Modern terminals expect UTF-8, so print the code point, not the byte. */
    printf("\u00D0\n");   /* UTF-8: C3 90 */

    unsigned char b = 208;         /* the raw Windows-1252 byte */
    printf("%d 0x%02X\n", b, b);    /* 208 0xD0 */
    return 0;
}

Code Example

</>

#include <stdio.h>

int main(void) {
    /* Byte 208 is ╨ only on a console using code page 437
       (chcp 437 on Windows, or DOSBox). On a UTF-8 terminal the
       lone byte 0xD0 is invalid and prints as garbage, often �. */
    putchar(208);

    /* char is signed on x86, so a plain char holding 0xD0 is -48.
       Use unsigned char when you compare or index by byte value. */
    char c = (char)208;
    unsigned char u = 208;
    printf("\n%d %d\n", c, u);   /* -48 208 */

    /* Portable: print the Unicode character as UTF-8 instead. */
    printf("\u2568\n");          /* E2 95 A8 */
    return 0;
}

How to Type It

Windows: Hold Alt and type 0208 on the numeric keypad, with Num Lock on. The leading zero picks the Windows code page. No numeric keypad? In Word, type 00D0 and press Alt+X.
Mac: Press Control+Command+Space to open the Character Viewer, then search for "latin capital letter eth".
Linux: In GNOME, or any desktop running IBus, press Ctrl+Shift+U, type d0, then Space. With a Compose key set up, press Compose, D, H.
Phone: Add the Icelandic keyboard in your phone's keyboard settings and type Ð there, or tap the character at the top of this page to copy it.

How to Type It

Windows: Hold Alt and type 208 on the numeric keypad, with no leading zero. US PCs insert ╨, but PCs set to code page 850, common in Western Europe, insert ð. No numeric keypad? In Word, type 2568 and press Alt+X.
Mac: Press Control+Command+Space to open the Character Viewer, then search for "box drawings up double and horizontal single".
Linux: In GNOME, or any desktop running IBus, press Ctrl+Shift+U, type 2568, then Space.
Phone: Phone keyboards have no key for it. Tap the character at the top of this page to copy it.

Frequently Asked Questions

Use d, which gives Gudrun. That's the standard fallback, and it's what Icelandic passports print in their machine-readable line. Watch out for the usual accent-stripping trick: ð has no decomposition, so NFKD plus dropping non-ASCII deletes it and leaves Gurun. A transliteration library such as Python's unidecode maps it to d properly.
Ð is the voiced th of English this, and Þ (byte 222) is the voiceless th of thin. They also split by position: þ starts words, as in Þór and það, while ð only turns up inside or at the end of a word, as in Guðrún and góð. Both are separate letters in Icelandic, not variants of d or t.

ASCII 208

Uppercase ethBox T-junction pointing up, double vertical

ASCII 208 is Ð on Windows and ╨ in old DOS.

Latin Letter

Box Drawing

#include <stdio.h>

int main(void) {

/* On Windows (code page 1252) byte 208 is Ð.

Modern terminals expect UTF-8, so print the code point, not the byte. */

printf("\u00D0\n"); /* UTF-8: C3 90 */

unsigned char b = 208; /* the raw Windows-1252 byte */

printf("%d 0x%02X\n", b, b); /* 208 0xD0 */

return 0;

}

#include <stdio.h>

int main(void) {

/* Byte 208 is ╨ only on a console using code page 437

(chcp 437 on Windows, or DOSBox). On a UTF-8 terminal the

lone byte 0xD0 is invalid and prints as garbage, often �. */

putchar(208);

/* char is signed on x86, so a plain char holding 0xD0 is -48.

Use unsigned char when you compare or index by byte value. */

char c = (char)208;

unsigned char u = 208;

printf("\n%d %d\n", c, u); /* -48 208 */

/* Portable: print the Unicode character as UTF-8 instead. */

printf("\u2568\n"); /* E2 95 A8 */

return 0;

}