Updates and verifying downloads

Acira checks for new versions by itself, downloads them in the background and asks you once before it restarts. This page covers how that works, the Stable and Beta channels, how to check a downloaded installer, and the signing status of the beta.

How updates work

1. About 20 seconds after Acira starts, then every 2 hours, and again when your computer wakes, it checks Acira's public update feed. It asks update.acirabrowser.com first and the older GitHub feed if that does not answer.
2. If a newer version exists, Acira downloads it in the background. A small dot matrix beside the Acira menu button fills as the download progresses. Hover over it to see the percent, the size and the speed.
3. When the download is complete, Acira asks once, in a popup titled Update ready: Install now, Later or Read more. Read more shows the whole list of changes in that version.
4. Install now saves your open tabs and windows and restarts Acira into the new version, with your tabs and profile as they were. If Settings › Tabs › When Acira starts is set to Open a New Tab, you start on a New Tab instead and your earlier tabs are in Rewind.

New versions are published on update.acirabrowser.com only. The GitHub feed that earlier betas read stops at beta.11 and is not written to any more. So a copy older than beta.11 first finds beta.11 on GitHub, installs it, and then asks update.acirabrowser.com, where it finds the newer beta on its first check, about 20 seconds after it starts. A copy that has been switched off for months does the same.

If you choose Later, Acira does not ask again for that version. An Update pill stays beside the Acira menu button, and a Restart to update row appears at the top of the Acira menu, so you can restart when it suits you. If you ignore it, the update installs when you quit Acira.

The first time Acira starts on a new version, a popup titled Acira updated to followed by the version shows the whole list of changes under What's new, one item to a line with room between them, and a Close button. A long list scrolls. If the release has no notes, a short message says Acira updated to followed by the version instead.

Check for updates yourself

1. Open Settings with Ctrl+, (Cmd+, on a Mac) and choose About.
2. In the Updates group, find the row that reads Acira, the release and the Chromium version, for example Acira Beta 13 (Chromium 152). The release is named the way the beta is: Beta 13 is version 0.1.0-beta.13.
3. Choose Check for updates.

The row then reports one of these states: Checking for updates…, Version and a number is available. (with a Download button), Downloading version and a percent, Version and a number is ready. Restart to install it. (with a Restart to update button), Acira is up to date. or Could not check for updates. followed by the reason.

Update settings

For the whole About section, see All settings.

When updates are not available

Updating works for an installed copy of Acira. In other cases, the update row is greyed out and gives the reason.

How an update is verified

• The update feed is public. You need no account to download an update, and Acira contains no sign-in token for it.
• Before it installs, Acira checks the downloaded file against a SHA-512 value published with the update. A file that does not match is not installed.
• Windows builds of the beta are not code-signed, so Windows cannot check a publisher. The SHA-512 check is what Acira relies on.
• On a Mac, the installed app must pass a macOS signature check before updates are allowed.

Verify a download

Every release on the releases page lists SHA-256 checksums in a file named SHA256SUMS.txt. Compare the checksum of the file you downloaded with the line for that file. If they match, the file arrived complete and is the file that was published. Get both files from Download Acira, and put them in your Downloads folder.

Windows (PowerShell)

1. Open PowerShell from the Start menu.
2. Go to your Downloads folder:

   cd $HOME\Downloads

3. Print the checksum of the installer:

   Get-FileHash .\AciraBrowserSetup.exe -Algorithm SHA256

4. Print the published line for the same file:

   Select-String -Path .\SHA256SUMS.txt -Pattern 'AciraBrowserSetup\.exe\s*$'

5. Compare the long hexadecimal values. Letter case does not matter.

To let PowerShell compare them, run these three lines. The last one prints True when they match:

$want = ((Select-String -Path .\SHA256SUMS.txt -Pattern 'AciraBrowserSetup\.exe\s*$').Line -split '\s+')[0]
$have = (Get-FileHash .\AciraBrowserSetup.exe -Algorithm SHA256).Hash
$have -eq $want

If you did not download the file with the name shown, replace AciraBrowserSetup.exe with the name of your file.

Mac (Terminal)

1. Open Terminal.
2. Go to your Downloads folder:

   cd ~/Downloads

3. Print the checksum of the DMG. Replace the file name in the example with the name of the file you downloaded. The name includes the version and arm64 for Apple silicon or x64 for Intel:

   shasum -a 256 AciraBrowser-VERSION-mac-arm64.dmg

4. Print the published line for the same file:

   grep 'AciraBrowser-VERSION-mac-arm64.dmg' SHA256SUMS.txt

5. Compare the long hexadecimal values.

To let the Mac compare them, run this line. It prints OK after the file name when they match:

grep 'AciraBrowser-VERSION-mac-arm64.dmg' SHA256SUMS.txt | shasum -a 256 -c

Linux (terminal)

In the folder with the AppImage and SHA256SUMS.txt, run this line. It prints OK after the file name when they match:

grep 'linux-x86_64.AppImage' SHA256SUMS.txt | sha256sum -c

The setup files run the same check before they install anything.

Signing status

On a Mac, you can check the signature of the installed app in Terminal:

codesign --verify --deep --strict --verbose=2 /Applications/Acira*.app

The command should end with valid on disk.

Last updated November 8, 2026