Free beta · macOS 14+ · 4.8 MB

The text editor that opens before you let go of the keys.

TerseEditor is a native Mac editor for everyone who just wants to open a file. Instant cold start, paste that lands as clean plain text, syntax highlighting for 9 languages, and notes that save themselves. No account, no cloud, no price.

Download for Mac
unzip → drag to Applications
Apple silicon & Intel Works fully offline Plain .txt files
parser.swift
notes.txt
server.log
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// 10 MB file — opened before the window finished animating
func parseChunk(_ buf: Substring) -> [Token] {
var out: [Token] = []
for token in lexer.tokens(buf) {
switch token.kind {
case .ident: out.append("ident")
case .string: out.append("string")
default: continue
}
}
Swift · UTF-8 · LF Ln 226, Col 8 · Saved
4.8 MB
Whole universal app. Not a browser in a trench coat
0
Third-party dependencies in the binary
10 MB
Files open instantly; 20 MB+ view read-only, never a spinner
0 bytes
Telemetry, analytics or network calls

Everything you actually use.
Nothing you have to learn.

TerseEditor is written in Swift against native macOS text engines, so it behaves like a Mac app — and gets out of your way like a text field.

Instant

Opens in a blink

Double-click a file and it's already on screen. Native Swift and AppKit: no splash, no “loading workspace”, no extensions warming up.

Clean paste

Paste is plain. Always.

Copy from any website or Word: non-breaking spaces, zero-width characters and smart quotes are stripped the moment text lands. What you keep is honest UTF-8 with LF endings.

Highlighting

9 languages, zero setup

Swift, Python, JavaScript/TypeScript, JSON, HTML/XML, CSS, Shell, C/C++ and Rust — recognised by extension and by content, even inside a pasted note. Everything else opens as plain text: .txt .md .log .csv .ini .yaml .conf — if it's text, it opens.

Editing

Regex find & replace

A proper find bar with regex, whole-word and case toggles, a live match counter and one-undo Replace All. Plus line operations: move, duplicate, sort, dedupe.

Sessions

Tabs that survive restarts

Notes autosave as plain .txt files — point the folder at iCloud Drive and they follow you to the next Mac. Open files and tabs come back exactly as you left them.

Quick Note

Capture without switching

Hit ⌃⌥⌘N in any app: a small panel floats up, you paste, press Esc — saved as a note. The fastest way to strip formatting from anything.

Native Swift.
Not Electron.

TerseEditor ships as one tiny universal binary that talks straight to macOS. That's why it launches instantly, sips battery, respects your system appearance, and never asks you to update a runtime.

Memory, idle< 60 MB
Dependencies0
Network callsnone
Price$0

Questions, answered

Is it really free?

Free while in beta — no account, no trial, no feature gates. If that ever changes, you'll hear about it long in advance.

Is this a Notepad++ port?

No. It's an independent Mac app built from scratch in Swift, aimed at the same job: open any text file fast and edit it without ceremony.

Which Macs are supported?

macOS 14 Sonoma and later — one universal build for both Apple silicon and Intel Macs.

macOS says the file “was not opened”

Expected for the beta — it isn't notarised yet. In the dialog click Done (not “Move to Trash”), then open System Settings → Privacy & Security, scroll down and click “Open Anyway”. macOS asks exactly once. A notarised build is on the way, and an App Store release will follow later.

What about my data?

Nothing leaves your machine. Notes are plain .txt files in a folder you choose; there are no analytics, no crash pings, no sync service. Air-gapped Macs welcome.

Can it replace my IDE?

It isn't trying to. TerseEditor is the app you reach for between IDE sessions — configs, logs, snippets, that one file you need to fix right now.

Which files can I open?

Anything that's text — .txt .md .log .csv .json .html .yaml .ini .conf and source files in any language. TerseEditor reads UTF-8, UTF-16 and legacy Windows encodings (CP1251/1252) and always saves clean UTF-8. In Finder: right-click a file → Open With → TerseEditor.

Open a file. See what fast feels like.

Version 1.0.0 beta · macOS 14+ · Universal (Apple silicon & Intel) · free

Download TerseEditor

Beta build, not yet notarised — macOS will ask you to allow it once in System Settings. Details in the FAQ.

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