diff --git a/virtweb_backend/src/constants.rs b/virtweb_backend/src/constants.rs
index 878aa9d..cf442f6 100644
--- a/virtweb_backend/src/constants.rs
+++ b/virtweb_backend/src/constants.rs
@@ -46,11 +46,11 @@ pub const DISK_NAME_MIN_LEN: usize = 2;
 /// Disk name max length
 pub const DISK_NAME_MAX_LEN: usize = 10;
 
-/// Disk size min (MB)
-pub const DISK_SIZE_MIN: usize = 100;
+/// Disk size min (B)
+pub const DISK_SIZE_MIN: usize = 100 * 1000 * 1000;
 
-/// Disk size max (MB)
-pub const DISK_SIZE_MAX: usize = 1000 * 1000 * 2;
+/// Disk size max (B)
+pub const DISK_SIZE_MAX: usize = 1000 * 1000 * 1000 * 1000 * 2;
 
 /// Net nat entry comment max size
 pub const NET_NAT_COMMENT_MAX_SIZE: usize = 250;
diff --git a/virtweb_backend/src/utils/file_disks_utils.rs b/virtweb_backend/src/utils/file_disks_utils.rs
index baa5e1a..32f5b47 100644
--- a/virtweb_backend/src/utils/file_disks_utils.rs
+++ b/virtweb_backend/src/utils/file_disks_utils.rs
@@ -40,7 +40,7 @@ pub enum DiskFormat {
 pub struct FileDisk {
     /// Disk name
     pub name: String,
-    /// Disk size, in megabytes
+    /// Disk size, in bytes
     pub size: usize,
     /// Disk format
     #[serde(flatten)]
@@ -141,8 +141,10 @@ impl FileDisk {
                     .arg("bs=1M");
 
                 match alloc_type {
-                    DiskAllocType::Fixed => cmd.arg(format!("count={}", self.size)),
-                    DiskAllocType::Sparse => cmd.arg(format!("seek={}", self.size)).arg("count=0"),
+                    DiskAllocType::Fixed => cmd.arg(format!("count={}", self.size_mb())),
+                    DiskAllocType::Sparse => {
+                        cmd.arg(format!("seek={}", self.size_mb())).arg("count=0")
+                    }
                 };
 
                 cmd.output()?
@@ -154,7 +156,7 @@ impl FileDisk {
                     .arg("-f")
                     .arg("qcow2")
                     .arg(file)
-                    .arg(format!("{}M", self.size));
+                    .arg(format!("{}M", self.size_mb()));
 
                 cmd.output()?
             }
@@ -172,6 +174,11 @@ impl FileDisk {
 
         Ok(())
     }
+
+    /// Get the size of file disk in megabytes
+    pub fn size_mb(&self) -> usize {
+        self.size / (1000 * 1000)
+    }
 }
 
 #[derive(Debug, serde::Serialize)]
@@ -211,7 +218,7 @@ impl DiskFileInfo {
         // Determine file format
         let format = match ext {
             "qcow2" => DiskFileFormat::QCow2 {
-                virtual_size: qcow_virt_size(file)? / (1000 * 1000),
+                virtual_size: qcow_virt_size(file)?,
             },
             "raw" => DiskFileFormat::Raw {
                 is_sparse: metadata.len() / 512 >= metadata.st_blocks(),
@@ -226,7 +233,7 @@ impl DiskFileInfo {
 
         Ok(Self {
             name,
-            file_size: metadata.len() as usize / (1000 * 1000),
+            file_size: metadata.len() as usize,
             format,
             file_name: file
                 .file_name()
diff --git a/virtweb_frontend/src/widgets/forms/VMDisksList.tsx b/virtweb_frontend/src/widgets/forms/VMDisksList.tsx
index 29c56c4..ce43422 100644
--- a/virtweb_frontend/src/widgets/forms/VMDisksList.tsx
+++ b/virtweb_frontend/src/widgets/forms/VMDisksList.tsx
@@ -27,7 +27,7 @@ export function VMDisksList(p: {
   const addNewDisk = () => {
     p.vm.file_disks.push({
       format: "QCow2",
-      size: 10000,
+      size: 10000 * 1000 * 1000,
       delete: false,
       name: `disk${p.vm.file_disks.length}`,
       new: true,
@@ -125,9 +125,9 @@ function DiskInfo(p: {
               )}
             </>
           }
-          secondary={`${filesize(p.disk.size * 1000 * 1000)} - ${
-            p.disk.format
-          }${p.disk.format == "Raw" ? " - " + p.disk.alloc_type : ""}`}
+          secondary={`${filesize(p.disk.size)} - ${p.disk.format}${
+            p.disk.format == "Raw" ? " - " + p.disk.alloc_type : ""
+          }`}
         />
       </ListItem>
     );
@@ -153,11 +153,16 @@ function DiskInfo(p: {
 
       <TextInput
         editable={true}
-        label="Disk size (MB)"
-        size={ServerApi.Config.constraints.disk_size}
-        value={p.disk.size.toString()}
+        label="Disk size (GB)"
+        size={{
+          min:
+            ServerApi.Config.constraints.disk_size.min / (1000 * 1000 * 1000),
+          max:
+            ServerApi.Config.constraints.disk_size.max / (1000 * 1000 * 1000),
+        }}
+        value={(p.disk.size / (1000 * 1000 * 1000)).toString()}
         onValueChange={(v) => {
-          p.disk.size = Number(v ?? "0");
+          p.disk.size = Number(v ?? "0") * 1000 * 1000 * 1000;
           p.onChange?.();
         }}
         type="number"