If you do not have unallocated space, right-click your main drive (usually C:) and select Shrink Volume .
The process is straightforward: launch the program, select your file system format (typically NTFS for modern Windows systems or FAT32 for compatibility), type in the desired "Display Size" (e.g., 150 GB), and click calculate. The tool instantly returns the exact MB value you must enter during the partition creation stage.
A "1TB" drive you buy often shows up in Windows as roughly 931 GB. hard disk partition calculator download free
Use the slider or enter the amount of space to take from the main drive.
Most users assume that a 1 Terabyte (TB) hard drive equals 1,000 Gigabytes (GB). However, computers operate in binary (Base-2), where 1 TB equals 1,024 GB. To make matters more confusing, hard drive manufacturers market drives in decimal (Base-10), where 1 TB equals 1,000 GB. If you do not have unallocated space, right-click
If you want a dedicated utility to handle these calculations or manage the actual partitioning, these are the top-rated free options:
Eliminates trial-and-error when splitting or resizing drives. Top Hard Disk Partition Calculators (Free Download) A "1TB" drive you buy often shows up
For Windows systems, use the NTFS file system for better performance and support for large files. Conclusion
| Tool | Platform | Key Feature | |------|----------|--------------| | (includes calculator) | Windows/Linux | Live USB + built-in size calculator | | EaseUS Partition Master Free | Windows | Visual slider + numeric entry | | MiniTool Partition Wizard Free | Windows | Partition size calculator dialog | | HDD Partition Calculator (standalone) | Windows Portable | Simple GUI for GB ↔ MB ↔ Cylinder | | Paragon Partition Manager Community | Windows | Free edition with alignment calculator |
Supports NTFS-to-FAT32 conversion without data loss, safe partition merging.
Choose your target GB size and apply the formula
