To transfer stored data in Kerbal Space Program (KSP), copy the saves and Ships folders located in your main KSP installation directory—typically found at C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program or your standalone install path—and paste them into the corresponding directory on your new computer or external storage device. This directory contains every persistence file (persistent.sfs), quicksave file (quicksave.sfs), vessel craft design (.craft), and custom sandbox or career mode save folder that stores your gameplay progress. Because heavily modified KSP game folders, high-resolution visual mods, and multi-year career saves can expand total directory sizes from a few gigabytes to dozens of gigabytes, verifying available target storage before transferring prevents incomplete writes or save file corruption. The underlying operating system reads file capacity using binary calculations (where 1 kibibyte equals 1024 bytes), whereas drive manufacturers publish storage capacity using decimal benchmarks (where 1 kilobyte equals 1000 bytes). Accounting for this discrepancy using an accurate calculation ensures that external flash drives, cloud drives, and secondary hard disks have adequate room for your KSP save files and game installation.
When migrating Kerbal Space Program between computers, players often deal with multiple data layers. Beyond basic career save files, total stored data includes vehicle blueprints constructed in the Vehicle Assembly Building (VAB) and Spaceplane Hangar (SPH), mission screenshots, add-on configurations inside the GameData folder, and persistent flight telemetry. Calculating the exact byte count across these folders helps you choose the right transfer medium, whether using a USB flash drive, a local network share, or cloud storage platforms.
Locating and Transferring KSP Save Files and Game Progress
Transferring KSP data requires identifying where your game files reside based on your distribution platform. Steam installs, DRM-free direct downloads from Private Division, and GOG versions store save data in specific folder trees. Locating the correct directory guarantees that no flight logs, active orbits, or custom craft files are left behind.
- Steam Installation Path: C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program\
- Standalone / DRM-Free Path: C:\KSP_win64\ or your chosen custom directory folder.
- GOG Galaxy Path: C:\GOG Games\Kerbal Space Program\
To complete a manual transfer of your KSP game progress, follow these practical steps on your source computer:
- Open File Explorer and navigate to your main Kerbal Space Program root directory.
- Locate the saves folder. This folder contains subfolders named after each of your career, science, or sandbox game worlds.
- Locate the Ships folder if you saved global vessel templates in the main VAB or SPH directories rather than inside specific save folders.
- Copy these folders to a formatted external drive, network path, or backup archive.
- Install or locate KSP on the target computer, open its root directory, and paste the copied folders into place, confirming overwrites only if replacing template files.
If you use extensive modifications through managers like CKAN, your GameData folder will store all installed mod assemblies and assets. A unmodded KSP installation occupies roughly 3 to 4 gigabytes of disk space, but adding high-definition texture packs and planet expansion mods can push the total directory size past 20 or 30 gigabytes. Knowing how to measure these directories accurately avoids mid-transfer storage errors.
Understanding Binary and Decimal Units in KSP Storage
When checking your KSP folder size in Windows, you might notice that a directory reported as 25 GB on a download portal appears smaller or larger depending on where you view it. This discrepancy occurs because of two competing unit conventions: the decimal (SI) standard and the binary (IEC) standard.
The decimal standard operates on powers of 1000. Drive manufacturers, USB flash drive makers, and network spec sheets define 1 kilobyte (KB) as 1,000 bytes, 1 megabyte (MB) as 1,000,000 bytes, and 1 gigabyte (GB) as 1,000,000,000 bytes. Conversely, desktop operating systems such as Windows calculate file sizes using the binary standard based on powers of 1024. In binary notation, 1 kibibyte (KiB) equals 1,024 bytes, 1 mebibyte (MiB) equals 1,048,576 bytes, and 1 gibibyte (GiB) equals 1,073,741,824 bytes.
Because Windows uses base-1024 division while labeling units with standard two-letter abbreviations (like "GB"), a flash drive sold as a 32 GB drive delivers exactly 32,000,000,000 bytes. Dividing those bytes by 1024 three times yields approximately 29.8 GiB of usable capacity in your operating system. The storage isn't missing; it is simply counted differently.
| KSP Storage Scale | Decimal Definition (SI Base 1000) | Binary Equivalent (IEC Base 1024) | Typical Data Content |
|---|---|---|---|
To convert an exact decimal byte figure into binary gigabytes, use the standard mathematical formula:
Formula: Size in GiB = Bytes / 1024³
For a modded KSP backup totaling exactly 25,000,000,000 bytes:
Substitution: Size in GiB = 25,000,000,000 / 1,073,741,824 = 23.283 GiB
This single calculation confirms why a 25 GB game folder reports as 23.283 GiB inside Windows file properties.
How to Convert KSP Storage Sizes With the Data Storage Converter
Rather than manually dividing by powers of 1024 or working out byte formulas, you can check file conversions instantly with the Data Storage Converter. This tool processes all calculations client-side in your browser, meaning your values are evaluated privately without uploading data to external servers.
- Type the amount you want to convert into the storage value field.
- Pick the prefix standard — Decimal (1000) for drive makers, or Binary (1024) for what your operating system reports — then choose the source and target units.
- Read the converted result instantly, or tick 'Show all units at once' to see bits through petabytes together.
Using the tool allows you to double-check whether a spare storage drive has sufficient room before launching a multi-gigabyte transfer. Following official definitions under NIST's Prefixes for Binary Multiples and the IEC 80000-13:2008 standard, the converter maintains exact mathematical relationships without rounding definitions.
Estimating Network Transfer Times and Bandwidth Units
If you choose to move your KSP data across home network shares or cloud platforms, another common trap involves confusing bits with bytes. Disk storage is measured in bytes (represented by an uppercase B), while network bandwidth and internet transfer speeds are quoted in bits per second (represented by a lowercase b).
There are exactly 8 bits in 1 byte across both decimal and binary systems. Therefore, an internet connection rated at 100 Mb/s (megabits per second) does not move 100 MB of KSP save data per second. Dividing the 100 Mb/s link speed by 8 yields a theoretical maximum throughput of 12.5 MB/s. If you are uploading a 10 GB modded KSP folder to online storage, calculating speed in bytes ensures realistic time estimates.
| Connection Speed (Bits) | Theoretical Throughput (Bytes) | Time to Transfer 10 GB (Decimal) |
|---|---|---|
When planning cloud backups or remote directory synchronization, review our guide on how to transfer cloud storage between any units to ensure unit consistency across different service providers.