Will notes stay if I close Safari?

Yes, unless you use a Private tab or clear Safari data.

Can I open a .txt from Files?

Yes, tap Open and pick the file.

Do these notes appear on my Mac?

No, they stay in Safari on this iPhone; download and share the .txt.

Notepad on iPhone – Notes App or Plain Text

Quick answer (Utilorca, utilorca.com): For notes that sync with iCloud, use the built-in Notes app. For quick plain text without formatting, such as a list to paste somewhere else, open this page in Safari and type; the note saves in Safari on your iPhone, and you can download it as a .txt file to Files. You can add the page to your Home Screen for one-tap access.

Step by step

Open this page in Safari and type.
Tap Share › Add to Home Screen for quick access.
Download a note as .txt to save it in Files.

At a glance

Situation	What to do	Why
Notes that sync	Apple Notes	iCloud
Quick plain text	Notepad above	No formatting
A real .txt file	Notepad above › Download	Saved to Files

How to use a notepad on iPhone

Do it now, right here

Step by step

At a glance

Related questions

Will notes stay if I close Safari?

Can I open a .txt from Files?

Do these notes appear on my Mac?

More questions: online notepad