diff --git a/src/ebml.rs b/src/ebml.rs
index ea7bf10..b23ee57 100644
--- a/src/ebml.rs
+++ b/src/ebml.rs
@@ -117,7 +117,7 @@ const EIGHT_MAX: u64 = EIGHT_FLAG - 2;
 pub fn encode_varint(varint: Varint, buffer: &mut [u8]) -> Result<usize, WriteError> {
     let (size, number) = match varint {
         Varint::Unknown => (1, 0xFF),
-        Varint::Value(too_big) if too_big >= EIGHT_MAX => {
+        Varint::Value(too_big) if too_big > EIGHT_MAX => {
             return Err(WriteError::OutOfRange)
         },
         Varint::Value(value) => {
@@ -246,6 +246,33 @@ mod tests {
         assert_eq!(encode_varint(Varint::Value(128), &mut buffer), Ok(2));
         assert_eq!(&buffer[0..2], &[0x40, 128]);
         assert_eq!(encode_varint(Varint::Value(128), &mut no_space), Err(WriteError::BufferTooSmall));
+
+        // 6 bytes
+        assert_eq!(encode_varint(Varint::Value(0x03FFFFFFFFFE), &mut buffer), Ok(6));
+        assert_eq!(&buffer[0..6], &[0x07, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE]);
+
+        // 7 bytes
+        assert_eq!(encode_varint(Varint::Value(0x03FFFFFFFFFF), &mut buffer), Ok(7));
+        assert_eq!(&buffer[0..7], &[0x02, 0x03, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]);
+
+        assert_eq!(encode_varint(Varint::Value(0x01000000000000), &mut buffer), Ok(7));
+        assert_eq!(&buffer[0..7], &[0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);
+
+        assert_eq!(encode_varint(Varint::Value(0x01FFFFFFFFFFFE), &mut buffer), Ok(7));
+        assert_eq!(&buffer[0..7], &[0x03, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE]);
+
+        assert_eq!(encode_varint(Varint::Value(0x01FFFFFFFFFFFE), &mut no_space), Err(WriteError::BufferTooSmall));
+        assert_eq!(encode_varint(Varint::Value(0x01FFFFFFFFFFFE), &mut buffer[0..6]), Err(WriteError::BufferTooSmall));
+
+        // 8 bytes
+        assert_eq!(encode_varint(Varint::Value(0x01FFFFFFFFFFFF), &mut buffer), Ok(8));
+        assert_eq!(&buffer[0..8], &[0x01, 0x01, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]);
+
+        assert_eq!(encode_varint(Varint::Value(0xFFFFFFFFFFFFFE), &mut buffer), Ok(8));
+        assert_eq!(&buffer[0..8], &[0x01, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE]);
+
+        assert_eq!(encode_varint(Varint::Value(0xFFFFFFFFFFFFFF), &mut buffer), Err(WriteError::OutOfRange));
+        assert_eq!(encode_varint(Varint::Value(u64::max_value()), &mut buffer), Err(WriteError::OutOfRange));
     }
 
     #[test]