Various embodiments provide techniques to determine a TBS for use with 1024 QAM communications that use more than one multiple input, multiple output (MIMO) layer based on a reference TBS for use with 1024 QAM communications that use a single MIMO layer. The reference TBS may be determined based on a TBS index and a resource allocation for the communication. The TBS index may be determined based on a modulation and coding scheme (MCS) index. Other embodiments may be described and claimed.