Caxton
Features Benchmarks Pricing Docs Support Download

Open a 10 GB log instantly. Edit it like it's ten kilobytes.

Caxton is a native macOS editor for the files that other editors refuse: production logs, database exports, ten-million-row CSVs. Memory-mapped, fully indexed, AppKit top to bottom. No Electron involved.

Download for macOS Read the benchmarks
14-day trial, no card · $9.99/mo · $99.99/yr · $179.99 lifetime
Private by default — your files stay on your Mac. No upload, no cloud processing, no telemetry. Privacy policy
Caxton holding a 10 GB server log — 80,610,954 lines, fully indexed, syntax-colored

Not a mockup — this is Caxton holding the 10 GB benchmark log. 80,610,954 lines in the status bar.

Built for SREs on call data engineers DBAs QA engineers analysts
caxton › what it does

Three workflows Mac editors still struggle with.

The workflows that have been exclusive to EmEditor on Windows for fifteen years, rebuilt as a native Mac app.

A 10 GB file is the design target, not the failure mode.

Memory-mapped I/O, a piece-table document model, and a tiered line index that scales past 120 million lines. The full file opens and indexes by default — no slicing required — but a Large File Controller is there when you only want a byte range of something truly enormous. The viewport renders only what you can see, so a 500 MB single-line minified bundle scrolls like a config file.

  • Open a 10 GB log, usable at once immediate
  • Full 80.6M-line background index 19.5 s measured
  • Sustained scroll, 80M+ lines 60 fps
  • Memory footprint on a 10 GB document under 200 MB measured
  • Large File Controller for partial opens optional, never required
  • Follow-tail for growing logs built in

A spreadsheet grid that runs at log-file speed.

CSV mode auto-detects delimiters, freezes headers, and sorts millions of rows by any column — click the header, get an external merge sort. Type inference runs underneath so numeric columns sort as numbers, and malformed rows get explicit parse states instead of silent guesses.

Caxton's CSV grid holding two million sales rows with typed columns and frozen headers

Two million rows of order data in the grid — click any header to sort, double-click any cell to edit.

  • Parse 1 GB · 2M rows × 50 columns to grid 2.6 s measured
  • Sort 2M rows by a numeric column 8.2 s measured
  • Sort any column from its header, numeric or text one click
  • Split, combine, extract, dedupe columns built in

Grep, but you can still scroll it.

Filter an 80-million-line file and see the first matches in under a second. Compose regex with level, time, and numeric-range filters; save the combinations you use every week. Slice mode shows matches in place with full surrounding context.

Caxton filtering a one-gigabyte log to only its ERROR lines — original line numbers preserved

Filtered to ERROR — 160,846 matching lines out of 8 million, original line numbers preserved, applied in about a quarter of a second.

caxton › benchmarks

We publish the numbers. The ones marked measured are real.

Caxton ships behind a 13-class benchmark matrix covering every file shape that breaks editors — huge logs, wide CSVs, single-line bundles, mixed encodings. These are the headline rows.

Operation
File
Status
Result
Open, scroll, edit
10 GB log · 80.6M lines
MEASURED
immediate
Full background index
10 GB log · 80.6M lines
MEASURED
19.5 s
Find, 1.61M matches
10 GB log
MEASURED
1.3 s
Regex alternation, 5.64M matches
10 GB log
MEASURED
2.1 s
Replace All, 1.61M replacements
10 GB log
MEASURED
1.7 s
Filter, level=ERROR
80.6M lines · 1.6M matches
MEASURED
1.3 s
CSV parse to grid
1 GB · 2M rows × 50 cols
MEASURED
2.6 s
CSV sort, numeric column
1 GB · 2M rows × 50 cols
MEASURED
8.2 s
Save after scattered edits
10 GB log · atomic rewrite
MEASURED
11.3 s
Keystroke apply latency
10 GB document
MEASURED
≈ 1 ms
One keystroke, 1,000 cursors
10 GB document
MEASURED
< 120 ms
Find in a single-line file
500 MB minified JS · one line
MEASURED
0.5 s

MEASURED = recorded by Caxton's in-app benchmark harness on an M1 Max MacBook Pro (64 GB), macOS 15.7, internal SSD, Release build, warm cache. Every number is count-verified — the find rows assert the exact match count, the Replace All row re-finds all 1,613,344 replacements afterward. Methodology and the full file-class matrix are in the docs.

Those numbers run on your files too. Download for macOS 14 days free · no card
caxton › who it's for

Who uses Caxton?

02:14:07.881ERRORsite_reliabilityinspecting production logs without waiting — follow-mode on, filter set to ERROR
09:31:42.118INFO data_engineercleaning multi-GB CSVs and JSON exports before they ship to the warehouse
11:02:19.040WARN dbainspecting SQL dumps before importing them anywhere near production
14:48:55.213INFO qa_engineeranalyzing crash reports and test artifacts from a 4 GB run
16:20:08.667ERRORsecurity_analystreviewing massive audit logs, one suspicious session at a time
18:05:33.902INFO researcherexploring large datasets directly — no preprocessing, no subsampling
caxton › why native

No Electron. No web view. No plugin runtime. AppKit and Swift, top to bottom.

  • Memory-mapped I/O. The architecture browsers can't offer.
  • ~200 MB idle on a 10 GB document.
  • Native tabs, Quick Look, Services menu — real Finder citizenship.
  • System dark mode through actual appearance APIs.
  • The real Mac print dialog, for the three people who print logs. We see you.
Caxton in its dark appearance Caxton in its light appearance

The same 10 GB document, both appearances — switched through the real macOS appearance APIs, not a CSS theme.

caxton › pricing

One product, all features, two ways to pay.

Try first: download Caxton and the 14-day trial starts on its own — no credit card, no account. Buy whenever you're convinced.

Monthly
$9.99
per month · cancel anytime
  • All v1 features
  • Free updates while subscribed
  • Works offline with a 30-day grace period
  • Email support
Buy monthly
Annual · two months free
$99.99
per year · cancel anytime
  • Everything in monthly
  • Priority support
  • Early access to 1.x features
Buy annual
Lifetime · launch price
$179.99
once · updates included
  • Pay once, own it
  • Every future update included
  • Priority support
  • No renewal, ever
Buy lifetime

If your subscription lapses, your files are never held hostage. Caxton stays installed and opens everything in read-only mode — view, search, copy, export. Resubscribe whenever you need to edit again.

Buying for a team? Volume licensing with invoice billing is available from day one — sales@caxton.app.

The file is already on your disk. Open it.

14 days free, no credit card. Apple Silicon and Intel.

Download Caxton for macOS Benchmarks first
macOS 13.0+ · v1.0.0 · notarized · SHA-256 published with every release