What is box breathing?

Box breathing is a breathing technique where you inhale for 4 counts, hold for 4, exhale for 4, and hold again for 4. It's used to reduce stress, ease anxiety, and reset focus — practiced by athletes, military personnel, and anyone who wants to quickly calm their nervous system.

How does BreatheFill work?

Click the BreatheFill icon in your Chrome toolbar. A calm orb appears and guides you through a breathing session — it fills as you inhale, holds still, then empties as you exhale. One full session takes 90 seconds. No setup required.

Yes, completely free. No in-app purchases, no subscriptions, no ads.

Does BreatheFill collect any personal data?

No. BreatheFill makes zero network requests. Your settings and weekly breath count are stored locally on your device only using chrome.storage.local. No accounts, no analytics, no tracking of any kind.

What breathing patterns does BreatheFill support?

BreatheFill supports box breathing (4-4-4-4 counts), the 4-7-8 breathing technique (longer exhale for anxiety relief and sleep), and a quick two-count pattern for a fast reset.

BreatheFill — Box Breathing Extension for Chrome

One honest moment of calm

Built for the breath, not for engagement.

No streaks to protect, no feed to scroll. A soft orb fills as you breathe in, holds, and empties as you breathe out. That is the whole product.

Ninety seconds

A guided box cycle — 4 in, 4 hold, 4 out, 4 hold — with the count shown right on the orb. Pick 60s, 90s, or two minutes.

Three patterns

Box breathing by default, plus the 4-7-8 wind-down and a quick 2-count when you only have a moment.

Four quiet themes

Dawn, Forest, Dusk, and Mono — calm palettes, never loud. Match the orb to the time of day.

Reduced-motion mode

Prefer less movement? The orb steps instead of sweeps, and seeds itself from your system setting on first run.

A gentle reminder

A soft mark on the icon — never a popping notification. Off until you turn it on. A nudge, not a nag.

A weekly tally

A small count of breaths taken this week, kept only on your device and reset every Monday. Yours alone.

How it works

Three steps, then back to it.

Click the icon

BreatheFill opens right in your toolbar — no new tab, no login, no setup.

Follow the orb

Breathe in as it fills, hold as it rests, breathe out as it empties. The ring tracks your ninety seconds.

Carry on

“You’re done.” Close it and return to your day a little steadier. Breathe again anytime.

Private by construction

Collects nothing.
Everything stays on your device.

BreatheFill makes not a single network request. There is no account to create, no analytics to opt out of, and no code that touches the pages you visit. It asks for two permissions and nothing else.

storage alarms no host permissions

No accounts, no sign-in.Open it and breathe. There is nothing to set up.

No analytics, no tracking.Your weekly tally is a local count that never leaves the browser.

No access to your pages.No content scripts, no host permissions, no read of the sites you visit.

All code is bundled.Manifest V3 with a strict, self-only content policy. No remote code, ever.

Common questions

Things people ask before installing

What exactly is box breathing?

Box breathing is a simple technique: breathe in for 4 counts, hold for 4, breathe out for 4, hold again for 4. That's one cycle. It's sometimes called 4-4-4-4 or "tactical breathing" and it's been studied for stress relief, anxiety management, and focus. The idea is that slowing your exhale triggers your parasympathetic nervous system — your body's built-in off switch for the stress response.

What's the difference between box breathing and 4-7-8?

Box breathing uses equal counts (4·4·4·4) and is good for a quick midday reset or focus before a meeting. The 4-7-8 pattern — inhale 4, hold 7, exhale 8 — has a much longer exhale, which tends to be more sedating. A lot of people use 4-7-8 to wind down in the evening or ease anxiety. BreatheFill has both, plus a quick two-count for when you just need a fast reset.

Does it actually work, or is this just an app for people who want to feel productive?

Controlled breathing exercises have genuine physiological effects — heart rate, blood pressure, and cortisol all respond to slow, deliberate breathing. Whether a 90-second session makes a meaningful difference for you personally depends on how stressed you actually are and how consistently you use it. The honest answer: some people find it noticeably helpful, others don't feel much. It's free to try.

Does BreatheFill collect any of my data?

Nothing. The extension makes zero network requests — not during install, not during a session, not ever. Your settings and your weekly breath count live in chrome.storage.local on your own computer. Uninstalling removes everything. It asks for two Chrome permissions: storage (to remember your settings) and alarms (for the optional hourly reminder). No host permissions, no content scripts, no analytics.

Is it free? Is there a catch?

It's free. No subscription, no in-app purchase, no ad-supported tier, no premium paywall hiding the useful features. It's a small breathing timer. The catch is that there isn't one.

Box breathing,
the moment you need it.