diff --git a/core/fmt/fmt.odin b/core/fmt/fmt.odin
index fad2548c8..ab57209c3 100644
--- a/core/fmt/fmt.odin
+++ b/core/fmt/fmt.odin
@@ -1049,8 +1049,8 @@ _fmt_int_128 :: proc(fi: ^Info, u: u128, base: int, is_signed: bool, bit_size: i
 	_pad(fi, s)
 }
 // Units of measurements:
-__MEMORY_LOWER := " b kb mb gb tb pb eb"
-__MEMORY_UPPER := " B KB MB GB TB PB EB"
+__MEMORY_LOWER := " b kib mib gib tib pib eib"
+__MEMORY_UPPER := " B KiB MiB GiB TiB PiB EiB"
 // Formats an integer value as bytes with the best representation.
 //
 // Inputs:
@@ -1069,13 +1069,13 @@ _fmt_memory :: proc(fi: ^Info, u: u64, is_signed: bool, bit_size: int, units: st
 	div, off, unit_len := 1, 0, 1
 	for n := abs; n >= mem.Kilobyte; n /= mem.Kilobyte {
 		div *= mem.Kilobyte
-		off += 3
+		off += 4
 
 		// First iteration is slightly different because you go from
 		// units of length 1 to units of length 2.
 		if unit_len == 1 {
 			off = 2
-			unit_len  = 2
+			unit_len  = 3
 		}
 	}
 
diff --git a/tests/core/fmt/test_core_fmt.odin b/tests/core/fmt/test_core_fmt.odin
index 8928338b3..4459af609 100644
--- a/tests/core/fmt/test_core_fmt.odin
+++ b/tests/core/fmt/test_core_fmt.odin
@@ -42,18 +42,18 @@ test_fmt_memory :: proc(t: ^testing.T) {
 		expect(t, got == exp, fmt.tprintf("(%q, %v): %q != %q", format, args, got, exp), loc)
 	}
 
-	check(t, "5b",       "%m",    5)
-	check(t, "5B",       "%M",    5)
-	check(t, "-5B",      "%M",    -5)
-	check(t, "3.00kb",   "%m",    mem.Kilobyte * 3)
-	check(t, "3kb",      "%.0m",  mem.Kilobyte * 3)
-	check(t, "3KB",      "%.0M",  mem.Kilobyte * 3)
-	check(t, "3.000 mb", "%#.3m", mem.Megabyte * 3)
-	check(t, "3.50 gb",  "%#m",   u32(mem.Gigabyte * 3.5))
-	check(t, "001tb",    "%5.0m", mem.Terabyte)
-	check(t, "-01tb",    "%5.0m", -mem.Terabyte)
-	check(t, "2.50 pb",  "%#5.m", uint(mem.Petabyte * 2.5))
-	check(t, "1.00 EB",  "%#M",   mem.Exabyte)
-	check(t, "255 B",    "%#M",   u8(255))
-	check(t, "0b",       "%m",    u8(0))
+	check(t, "5b",        "%m",    5)
+	check(t, "5B",        "%M",    5)
+	check(t, "-5B",       "%M",    -5)
+	check(t, "3.00kib",   "%m",    mem.Kilobyte * 3)
+	check(t, "3kib",      "%.0m",  mem.Kilobyte * 3)
+	check(t, "3KiB",      "%.0M",  mem.Kilobyte * 3)
+	check(t, "3.000 mib", "%#.3m", mem.Megabyte * 3)
+	check(t, "3.50 gib",  "%#m",   u32(mem.Gigabyte * 3.5))
+	check(t, "01tib",     "%5.0m", mem.Terabyte)
+	check(t, "-1tib",     "%5.0m", -mem.Terabyte)
+	check(t, "2.50 pib",  "%#5.m", uint(mem.Petabyte * 2.5))
+	check(t, "1.00 EiB",  "%#M",   mem.Exabyte)
+	check(t, "255 B",     "%#M",   u8(255))
+	check(t, "0b",        "%m",    u8(0))
 }