There are several free Python obfuscation options available in 2025, each with different approaches, limitations, and trade-offs. Here is an honest comparison.
pyobfuscator.com
Approach: Browser-based, zlib + Base64 + reversal encode-and-execute. Privacy: 100% client-side -- your code never leaves your browser. Limits: None -- no account required, no file size cap. Output: A two-line .py file runnable on any Python 3 install with no extra dependencies. Best for: Quick, private, zero-setup obfuscation of any Python 3 script.
PyArmor (Free Tier)
Approach: Bytecode-level obfuscation with a custom runtime loader -- far more sophisticated than encode-and-execute. Privacy: Runs locally (CLI tool). Limits: Free tier limits the number of scripts and script size. Output: A directory with obfuscated .py files and a required runtime package. Best for: Stronger protection when the deployment complexity is acceptable.
Oxyry Python Obfuscator
Approach: Online tool that performs variable renaming and string mangling. Privacy: Code is processed server-side. Output: Obfuscated .py file with renamed identifiers. Best for: Variable-renaming obfuscation when server-side processing is acceptable.
Manual Base64/zlib One-Liner
Approach: Write it yourself in two lines of Python -- no tool needed. Privacy: 100% local. Output: Same pattern as pyobfuscator.com. Best for: Developers who want full control over the exact output format.
Which to Choose?
- Fastest, most private, no setup: pyobfuscator.com
- Strongest free protection: PyArmor free tier
- Variable renaming specifically: Oxyry (accepting server-side processing)
- Full control: Manual script