Skip to download
macOS 11+Chromium

A Calm Window on the web.

Casement is a desktop browser built on Chromium — real tabs, an AI form-filler, a keychain-sealed password vault, and history that never leaves your Mac.

Casement for macOS

Version 1.8.2 · macOS 11+ · Free

Download v1.8.2 for Apple SiliconLatest release · M1 · M2 · M3 · M4Install helpSetup wizard runs inside the appSigned & ready to openApple Silicon only
macOS
11 Big Sur or later
Chip
Apple Silicon (M1 or newer)
Memory
4 GB RAM minimum
Disk
115 MB download
Casement — New tab
casement.app
Go
RecallVaultPrivacyDownloads
Installation

Install Casement on macOS

Five steps, about a minute. Requires macOS 11 Big Sur or later.

  1. Download the right build

    Casement is built for Apple Silicon (M1, M2, M3, M4). Not sure? Apple menu → About This Mac shows your chip.

  2. Open the download

    Double-click the .dmg to mount it, or the .zip to unpack it. Finder puts Casement.app in your Downloads folder.

  3. Drag Casement to Applications

    Drop Casement.app into the Applications folder — that is the entire install. No installer, no background services. Eject the disk image when you're done.

  4. Open it the first time

    This build is signed and notarized by Apple, so double-clicking Casement in Applications just works — no right-click, no Terminal.

    Install troubleshooting →

  5. Sign in to sync (optional)

    Open Casement → Settings → Account and sign in to sync bookmarks, history and your encrypted vault across your Macs. Skip it and everything stays local.

Threads & panes

A window that keeps your work apart

Casement replaces the tab strip with threads: named, colored pages that live in workspaces, remember their own assistant context, and sleep when you aren't looking. Split the window into up to four panes and put the ones you need side by side.

Command palette
⌘K
Thread assistant
⌘J
Private thread
⌥⌘N
Resource monitor
⇧⌘M
Site controls
⇧⌘I
Focus a pane
⌘1–4

Threads, not tabs

A vertical rail of named, colored threads grouped into workspaces. Archive one to get it out of the way, hibernate the quiet ones, and pick them all back up on your other Mac.

Split windowing

Two, three or four panes — columns, rows or a grid — with draggable dividers, drag-and-drop between panes, and layouts you can name and restore.

Assistant per thread

⌘J opens an assistant that sees only the thread you asked from: the page, the selection, and that thread's own memory. Nothing leaks sideways.

It can act, carefully

Ask it to click, type, scroll or open a link and it does it in your page, step by step, with password fields off limits and a read-only switch in Settings.

Command palette

⌘K fuzzy-finds every command, thread, favorite and page you've visited. Selection actions float in-page for Explain, Summarize, Translate and Search.

Private threads

⌥⌘N opens a thread on an ephemeral partition — outside history, sync and session restore, and gone the moment you close it.

Resource monitor

⇧⌘M shows CPU and memory per thread, so you can see which page is spinning your fans, mute it, or exempt it from hibernation.

Per-site controls

⇧⌘I opens the site sheet: tracker blocking, camera, microphone, location, notifications and AI access, decided per domain and remembered.

PDFs you can mark up

PDFs open in Casement's own surface with thumbnails and selectable text. Highlight, add notes, and export a flattened copy with your marks baked in.

Reading list

Save anything for later beside your favorites, keep an unread count in the rail, and open a saved page straight into its own thread.

Reader & gestures

Reader mode strips a page to its text; a two-finger swipe moves back and forward per pane, with a rubber-band edge and a toggle if you'd rather it didn't.

Inside the app

A browser made of quiet parts

Every tile below is a piece of the build you can download on this page.

One quiet strip of chrome

Tabs, omnibox, favorites and every tool in a single hairline bar — no ribbons, no sidebars you didn't ask for.

Keychain-sealed vault

Encrypted to this Mac, with a rules-based generator and passphrase-sealed backups.

Privacy you can see

Trackers, cookies, HTTPS-only, DNT/GPC and clear-on-quit — one pane, no dark patterns.

Downloads with real controls

Live speed, pause, resume, reveal in Finder — and a folder you pick.

WebGPU on by default

Three.js scenes, Vue and React apps run at native Chromium speed.

Assistant in the chrome

⇧⌘F reads the form in front of you and fills it — passwords never reach the model.

Why another browser

Same engine. Opposite priorities.

Casement renders with the same Chromium that Chrome and Edge use, so sites behave identically. What changes is everything wrapped around it.

The assistant is in the chrome, not a tab

⇧⌘F reads the form you're looking at and fills it. Chrome and Safari autofill from a saved profile; Casement reasons about unfamiliar fields — and never sends password values to the model.

Passwords sealed to your Keychain

The vault file is encrypted with macOS safeStorage, so a stolen copy won't open on another Mac. Sync is end-to-end encrypted under a passphrase we can't recover.

No account, no telemetry, no sign-in wall

Casement ships with zero analytics and no ad stack. History lives in Recall on your Mac; sync only starts when you decide to sign in.

Full modern-web stack, switched on

WebGPU, WebGL2, WASM and SharedArrayBuffer are enabled, so three.js scenes, Vue and React apps and heavy canvases run at native Chromium speed.

One window's worth of memory

No feed, no sidebar apps, no crypto wallet, no rewards program. The whole UI is a toolbar, a favorites strip and sheets that appear when you call them.

Updates you can verify

Each update is checked against a published SHA-256 digest and installed with an atomic swap — only after you press the button.

CapabilityCasementChromeSafari
AI form fill built into the toolbarYesNoNo
Page → markdown reader (Firecrawl)YesNoNo
Password vault sealed to the KeychainYesGoogle accountiCloud
End-to-end encrypted vault syncPassphraseOptionalYes
Telemetry / ad platformNoneYesLimited
Per-site AI + scraping policyYesNoNo
Verified SHA-256 update channelYesAutoSystem
WebGPU + WASM threads on by defaultYesYesPartial
Chrome extensions

Your uBlock, your Vue Devtools, your Bitwarden.

Casement runs Chromium's extension system directly, so MV2 and MV3 extensions load from a folder — content scripts, background service workers, chrome.storage, chrome.runtime messaging and devtools panels included.

  • Content scripts, service workers, storage, messaging and devtools panels.
  • Ad blockers, password managers, Vue and React devtools, Grammarly-style helpers.
  • No Chrome Web Store one-click install, and no chrome.tabs write APIs — load unpacked instead.
  1. 01

    Unzip or clone the extension

    Any Chrome extension folder with a manifest.json works — download the .crx and unzip it, or grab the source from GitHub.

  2. 02

    Settings › Extensions › Load unpacked

    Point Casement at the folder. It loads into the browsing session immediately and re-loads on every launch.

  3. 03

    It runs on every tab

    Content scripts, background service workers, storage and message passing run against Chromium's own extension APIs.

Engineered for quiet focus

Threads & workspaces

Named, colored threads in a vertical rail, grouped into workspaces, archived or hibernated when quiet.

Page-aware assistant

⌘J answers about the page in front of you — and can click, type and scroll it when you ask.

Password vault

Encrypted with the macOS keychain, with a generator, TOTP codes and passphrase-sealed backups.

Reader & PDF markup

Strip a page to its text, or highlight and annotate PDFs and export a flattened copy.

Smart omnibox

Type a URL or a question — anything else falls through to search.

Recall

Every page you visit, searchable and clearable, stored only on your Mac.

Favorites & reading list

Pin what you return to, and keep a read-later queue with an unread count in the rail.

Glass, light & dark

Frosted chrome and hairline edges over a quiet marine palette.

Latest web specs

WebGPU, WebGL2, WASM and SharedArrayBuffer on — Three.js scenes and Vue apps run at full speed, plus Chrome extensions.

History and favorites stay on your machine unless you turn on sync.

Master the keys

New thread
⌘T
Command palette
⌘K
Thread assistant
⌘J
Private thread
⌥⌘N
Focus address bar
⌘L
Focus a pane
⌘1–4
Resource monitor
⇧⌘M
Site controls
⇧⌘I
AI-fill this form
⇧⌘F
Autofill password
⇧⌘A
Passwords
⇧⌘P
Recall history
⌘Y
Toggle theme
⇧⌘D
Picture-in-picture
⌥⌘P
What's new

Casement 1.8.2 for macOS

Released 15 August 2026Apple Silicon · 115 MBSigned & notarized

  • Split panes remember their layout per workspace, with snapping and a one-tap reset.
  • Customisable start-page tiles and bulk token import.
  • Tightened glass edging across the reading list and archive drawers.
  • Apple Silicon only, signed and notarized — installs without the Gatekeeper warning.
Get 1.8.2Read the 1.8.2 release notes →Upgrading from 1.7.x? Follow the checklist →Full changelog →

Changelog

Checked every six hours, verified against SHA-256, installed only when you say so.

  1. Casement 1.8.32026-08-15Not yet released
    • ·Find in page (⌘F) with a live match count, ⌘G / ⇧⌘G to step through hits and Esc to clear.
    • ·Workspace badges redesigned: squared-off chips with stronger active contrast, keyboard focus rings, clearer status dots and a hover tooltip showing the last site and when it was opened.
    • ·Fixed a false “Offline” banner — the connectivity probe now races several endpoints and needs two consecutive failures before it reports an outage.
    • ·Bookmarks manager in Settings: search, recategorise, rename and delete, with deletions syncing across Macs.
    • ·Imports now show a preview first — detected columns, manual column mapping and sample rows before anything is saved.
    • ·Wider token parsing: more otpauth:// variants, and base32 secrets with spaces, hyphens or look-alike characters.
    • ·Export passwords and tokens as CSV, RTF or JSON to move between Macs.
    • ·Import results summary with per-row reasons for anything skipped.
    • ·Graphics fix for Apple Silicon: the renderer is pinned to Metal (ANGLE Metal + Skia Graphite) instead of asking for a Linux-only backend, and Settings › About now reports the live GPU and WebGPU status.
    • ·App icon is packaged correctly again — no more generic Electron icon in the Dock.
  2. Casement 1.8.22026-08-15
    • ·Split panes remember their layout per workspace, with snapping and a one-tap reset.
    • ·Customisable start-page tiles and bulk token import.
    • ·Tightened glass edging across the reading list and archive drawers.
    • ·Apple Silicon only, signed and notarized — installs without the Gatekeeper warning.
  3. Casement 1.8.12026-08-15
    • ·Fixes the launch crash where the window opened but nothing responded — no clicks, no navigation, no sites loading.
    • ·Settings, Reader and the other overlays can always be dismissed again.
    • ·Apple Silicon only, signed and notarized, so it installs without the Gatekeeper warning.
    • ·Every download button on this site now serves this build.
  4. Casement 1.7.12026-08-14
    • ·Settings › Downloads lets you pick the folder Casement saves files to, reset back to the macOS Downloads folder, or open it.
    • ·New option to ask where to save each file instead of downloading straight to the folder.
    • ·Downloads with a name that already exists are numbered rather than overwritten, and an unavailable folder quietly falls back to Downloads.
    • ·Downloadable builds are now hosted directly, so the buttons on this site install the real app.
  5. Casement 1.7.02026-08-14
    • ·The password generator now has real rules: a length slider up to 128, per-set switches for a–z, A–Z, 0–9 and symbols, your own symbol list, characters to exclude, look-alike skipping and no-repeat mode.
    • ·A live strength meter shows the entropy your rules actually produce.
    • ·One click inserts a fresh password straight into the field you last used on the page — confirmation fields included — and copies it at the same time.
    • ·Your generator rules are remembered between launches.
  6. Casement 1.6.12026-08-14
    • ·Casement now checks for updates on its own — every few hours, on wake from sleep and when you come back to the window.
    • ·A quiet prompt appears above the page when a new build is ready, with release notes and a one-click install.
    • ·"Later" holds a non-critical update for a day; security releases stay visible until installed.
    • ·Settings › Updates shows the Chromium version behind Casement and when it last checked.
  7. Casement 1.6.02026-08-14
    • ·Sealed vault backups: export every saved login to a single file encrypted with a passphrase you choose.
    • ·Restore on any Mac — pick a backup and Casement shows the sites and entry count before you unlock it.
    • ·Merge or replace on restore, with a preview that shows exactly what will change before anything is written.
    • ·CSV import from Chrome, Safari, 1Password and Bitwarden, plus a clearly-labelled plaintext CSV export.
  8. Casement 1.5.02026-08-14
    • ·Casement can now update itself: verified downloads, release notes and a one-click install.
    • ·Updates are checked every six hours, downloaded in the background and pinned to a SHA-256 checksum.
    • ·New Updates pane in Settings with channel, auto-check and auto-download controls.
    • ·The previous version is kept on disk until the new build launches cleanly.
  9. Casement 1.4.02026-08-14
    • ·Full settings page: privacy controls, proxy and secure DNS, per-site permissions and theme behaviour.
    • ·Tracker blocking, third-party cookie blocking, HTTPS-only mode and Do Not Track.
    • ·Granular clear-browsing-data, including a clear-on-quit option.
  10. Casement 1.3.02026-08-13
    • ·Built-in download manager with progress, speed, ETA, pause/resume and Show in Finder.
    • ·Downloads persist across launches and the panel opens automatically on a new transfer.