About Substitution Cipher
Substitution Cipher is a free, fast and reliable online tool. Encrypt with a custom substitution alphabet. You can configure Text and Cipher alphabet (26 letters) to get the result. Everything runs locally in your browser — no files are uploaded and no data is stored, keeping your information completely private. It works responsively on both desktop and mobile devices.
How to use Substitution Cipher
- 1 Enter Text and Cipher alphabet (26 letters)
- 2 Click "Convert"
- 3 Review the result and click "Copy"
Frequently asked questions
How do I use Substitution Cipher?
Enter Text and Cipher alphabet (26 letters) and the result is calculated instantly in your browser.
Is Substitution Cipher free to use?
Yes — Substitution Cipher is a free online tool. No sign-up or login is required, and there are no hidden charges or usage limits.
Do I need to create an account to use Substitution Cipher?
No. Substitution Cipher runs entirely online in your browser — there is no account to create, no login, and nothing to install.
Does Substitution Cipher upload my data?
No. Everything runs locally in your browser. Your input never leaves your device, is never stored, and is never tracked, so it stays private.
Free, online, and private
Free to use
Substitution Cipher is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.