diff --git a/pbs-api-types/src/human_byte.rs b/pbs-api-types/src/human_byte.rs
index a82d8fe8..413df35d 100644
--- a/pbs-api-types/src/human_byte.rs
+++ b/pbs-api-types/src/human_byte.rs
@@ -1,50 +1,206 @@
-pub struct HumanByte {
-    b: usize,
+use anyhow::{bail, Error};
+
+/// Size units for byte sizes
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub enum SizeUnit {
+    Byte,
+    // SI (base 10)
+    KByte,
+    MByte,
+    GByte,
+    TByte,
+    PByte,
+    // IEC (base 2)
+    Kibi,
+    Mebi,
+    Gibi,
+    Tebi,
+    Pebi,
 }
-impl std::fmt::Display for HumanByte {
+
+impl SizeUnit {
+    /// Returns the scaling factor
+    pub fn factor(&self) -> f64 {
+        match self {
+            SizeUnit::Byte => 1.0,
+            // SI (base 10)
+            SizeUnit::KByte => 1_000.0,
+            SizeUnit::MByte => 1_000_000.0,
+            SizeUnit::GByte => 1_000_000_000.0,
+            SizeUnit::TByte => 1_000_000_000_000.0,
+            SizeUnit::PByte => 1_000_000_000_000_000.0,
+            // IEC (base 2)
+            SizeUnit::Kibi => 1024.0,
+            SizeUnit::Mebi => 1024.0 * 1024.0,
+            SizeUnit::Gibi => 1024.0 * 1024.0 * 1024.0,
+            SizeUnit::Tebi => 1024.0 * 1024.0 * 1024.0 * 1024.0,
+            SizeUnit::Pebi => 1024.0 * 1024.0 * 1024.0 * 1024.0 * 1024.0,
+        }
+    }
+
+    /// gets the biggest possible unit still having a value greater zero before the decimal point
+    /// 'binary' specifies if IEC (base 2) units should be used or SI (base 10) ones
+    pub fn auto_scale(size: f64, binary: bool) -> SizeUnit {
+        if binary {
+            let bits = 63 - (size as u64).leading_zeros();
+            match bits {
+                50.. => SizeUnit::Pebi,
+                40..=49 => SizeUnit::Tebi,
+                30..=39 => SizeUnit::Gibi,
+                20..=29 => SizeUnit::Mebi,
+                10..=19 => SizeUnit::Kibi,
+                _ => SizeUnit::Byte,
+            }
+        } else {
+            if size >= 1_000_000_000_000_000.0 {
+                SizeUnit::PByte
+            } else if size >= 1_000_000_000_000.0 {
+                SizeUnit::TByte
+            } else if size >= 1_000_000_000.0 {
+                SizeUnit::GByte
+            } else if size >= 1_000_000.0 {
+                SizeUnit::MByte
+            } else if size >= 1_000.0 {
+                SizeUnit::KByte
+            } else {
+                SizeUnit::Byte
+            }
+        }
+    }
+}
+
+/// Returns the string repesentation
+impl std::fmt::Display for SizeUnit {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        if self.b < 1024 {
-            return write!(f, "{} B", self.b);
+        match self {
+            SizeUnit::Byte => write!(f, "B"),
+            // SI (base 10)
+            SizeUnit::KByte => write!(f, "KB"),
+            SizeUnit::MByte => write!(f, "MB"),
+            SizeUnit::GByte => write!(f, "GB"),
+            SizeUnit::TByte => write!(f, "TB"),
+            SizeUnit::PByte => write!(f, "PB"),
+            // IEC (base 2)
+            SizeUnit::Kibi => write!(f, "KiB"),
+            SizeUnit::Mebi => write!(f, "MiB"),
+            SizeUnit::Gibi => write!(f, "GiB"),
+            SizeUnit::Tebi => write!(f, "TiB"),
+            SizeUnit::Pebi => write!(f, "PiB"),
         }
-        let kb: f64 = self.b as f64 / 1024.0;
-        if kb < 1024.0 {
-            return write!(f, "{:.2} KiB", kb);
+    }
+}
+
+/// Byte size which can be displayed in a human friendly way
+pub struct HumanByte {
+    /// The siginficant value, it does not includes any factor of the `unit`
+    size: f64,
+    /// The scale/unit of the value
+    unit: SizeUnit,
+}
+
+impl HumanByte {
+    /// Create instance with size and unit (size must be positive)
+    pub fn with_unit(size: f64, unit: SizeUnit) -> Result<Self, Error> {
+        if size < 0.0 {
+            bail!("byte size may not be negative");
         }
-        let mb: f64 = kb / 1024.0;
-        if mb < 1024.0 {
-            return write!(f, "{:.2} MiB", mb);
-        }
-        let gb: f64 = mb / 1024.0;
-        if gb < 1024.0 {
-            return write!(f, "{:.2} GiB", gb);
-        }
-        let tb: f64 = gb / 1024.0;
-        if tb < 1024.0 {
-            return write!(f, "{:.2} TiB", tb);
-        }
-        let pb: f64 = tb / 1024.0;
-        return write!(f, "{:.2} PiB", pb);
+        Ok(HumanByte { size, unit })
+    }
+
+    /// Create a new instance with optimal binary unit computed
+    pub fn new_binary(size: f64) -> Self {
+        let unit = SizeUnit::auto_scale(size, true);
+        HumanByte { size: size / unit.factor(), unit }
+    }
+
+    /// Create a new instance with optimal decimal unit computed
+    pub fn new_decimal(size: f64) -> Self {
+        let unit = SizeUnit::auto_scale(size, false);
+        HumanByte { size: size / unit.factor(), unit }
+    }
+
+    /// Returns the size as u64 number of bytes
+    pub fn as_u64(&self) -> u64 {
+        self.as_f64() as u64
+    }
+
+    /// Returns the size as f64 number of bytes
+    pub fn as_f64(&self) -> f64 {
+        self.size * self.unit.factor()
+    }
+
+    /// Returns a copy with optimal binary unit computed
+    pub fn auto_scale_binary(self) -> Self {
+        HumanByte::new_binary(self.as_f64())
+    }
+
+    /// Returns a copy with optimal decimal unit computed
+    pub fn auto_scale_decimal(self) -> Self {
+        HumanByte::new_decimal(self.as_f64())
+    }
+}
+
+impl From<u64> for HumanByte {
+    fn from(v: u64) -> Self {
+        HumanByte::new_binary(v as f64)
     }
 }
 impl From<usize> for HumanByte {
     fn from(v: usize) -> Self {
-        HumanByte { b: v }
+        HumanByte::new_binary(v as f64)
     }
 }
-impl From<u64> for HumanByte {
-    fn from(v: u64) -> Self {
-        HumanByte { b: v as usize }
+
+impl std::fmt::Display for HumanByte {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let precision = f.precision().unwrap_or(3) as f64;
+        let precision_factor = 1.0 * 10.0_f64.powf(precision);
+        // this could cause loss of information, rust has sadly no shortest-max-X flt2dec fmt yet
+        let size = ((self.size * precision_factor).round()) / precision_factor;
+        write!(f, "{} {}", size, self.unit)
     }
 }
 
 #[test]
-fn correct_byte_convert() {
-    fn convert(b: usize) -> String {
+fn test_human_byte_auto_unit_decimal() {
+    fn convert(b: u64) -> String {
+        HumanByte::new_decimal(b as f64).to_string()
+    }
+    assert_eq!(convert(987), "987 B");
+    assert_eq!(convert(1022), "1.022 KB");
+    assert_eq!(convert(9_000), "9 KB");
+    assert_eq!(convert(1_000), "1 KB");
+    assert_eq!(convert(1_000_000), "1 MB");
+    assert_eq!(convert(1_000_000_000), "1 GB");
+    assert_eq!(convert(1_000_000_000_000), "1 TB");
+    assert_eq!(convert(1_000_000_000_000_000), "1 PB");
+
+    assert_eq!(convert((1 << 30) + 103 * (1 << 20)), "1.182 GB");
+    assert_eq!(convert((1 << 30) + 128 * (1 << 20)), "1.208 GB");
+    assert_eq!(convert((2 << 50) + 500 * (1 << 40)), "2.802 PB");
+}
+
+#[test]
+fn test_human_byte_auto_unit_binary() {
+    fn convert(b: u64) -> String {
         HumanByte::from(b).to_string()
     }
-    assert_eq!(convert(1023), "1023 B");
-    assert_eq!(convert(1 << 10), "1.00 KiB");
-    assert_eq!(convert(1 << 20), "1.00 MiB");
-    assert_eq!(convert((1 << 30) + 103 * (1 << 20)), "1.10 GiB");
-    assert_eq!(convert((2 << 50) + 500 * (1 << 40)), "2.49 PiB");
+    assert_eq!(convert(987), "987 B");
+    assert_eq!(convert(1022), "1022 B");
+    assert_eq!(convert(9_000), "8.789 KiB");
+    assert_eq!(convert(10_000_000), "9.537 MiB");
+    assert_eq!(convert(10_000_000_000), "9.313 GiB");
+    assert_eq!(convert(10_000_000_000_000), "9.095 TiB");
+
+    assert_eq!(convert(1 << 10), "1 KiB");
+    assert_eq!(convert((1 << 10) * 10), "10 KiB");
+    assert_eq!(convert(1 << 20), "1 MiB");
+    assert_eq!(convert(1 << 30), "1 GiB");
+    assert_eq!(convert(1 << 40), "1 TiB");
+    assert_eq!(convert(1 << 50), "1 PiB");
+
+    assert_eq!(convert((1 << 30) + 103 * (1 << 20)), "1.101 GiB");
+    assert_eq!(convert((1 << 30) + 128 * (1 << 20)), "1.125 GiB");
+    assert_eq!(convert((1 << 40) + 128 * (1 << 30)), "1.125 TiB");
+    assert_eq!(convert((2 << 50) + 512 * (1 << 40)), "2.5 PiB");
 }