How to Blur a Face in a Video (Free & Fast)

Why blur faces in a video?

Video is far more revealing than a still photo — a face appears across dozens or hundreds of frames, often from multiple angles. Blurring it before you share protects the people in the footage and keeps you on the right side of platform rules and privacy law. Common reasons:

• Bystanders in the background — street interviews, vlogs, event recordings, and travel clips routinely capture people who never consented to appear.
• Protecting minors — schools, sports clubs, and family videos often need faces hidden before anything is posted publicly.
• Journalism and whistleblower footage — a source or witness who asked to stay anonymous must not be identifiable in a published clip.
• Platform and compliance rules — many organisations require faces to be obscured in training videos, incident footage, or anything shared externally.
• Dashcam and security clips — before sharing an incident video, you may want to hide uninvolved people and plates.

Step-by-step: how to blur a face in a video (free)

Blurify processes video entirely in your browser using ffmpeg compiled to WebAssembly — your clip is never uploaded to a server. Here is the full workflow.

Step 1: Open your video

Go to blurify.me and drop your video onto the uploader, or click to browse. Blurify supports MP4, WebM, and MOV. The video loads straight into the editor with a timeline along the bottom — there is no upload step because the file stays on your device.

Step 2: Auto-detect faces, or draw a shape

The fastest path is the Detect Faces button in the toolbar. Blurify runs an on-device face-detection model (MediaPipe) that scans the video frame by frame, creates a blur shape for every face it finds, and adds keyframes so each blur follows its face through the clip — all without sending a single frame anywhere.

You can also do it manually: pick the Rectangle, Ellipse, or Freehand tool and draw over the face. The ellipse tends to look most natural on a head. Set the blur strength with the intensity slider — 20 or higher is recommended for reliable anonymization — or switch to Redact mode for a solid, unrecoverable black box.

Step 3: Track the face as it moves (keyframes)

If the face (or the camera) moves, a single fixed shape won't stay on target. Keyframes solve this. Scrub the timeline to a point where the face has moved, drag the blur shape back over it, and press K (or Add keyframe) to record its position at that moment. Blurify smoothly interpolates the blur between your keyframes, so it glides along with the face.

You only need a keyframe wherever the motion changes direction or speed — a few well-placed keyframes usually cover a whole clip. If you used Detect Faces, the keyframes are already there; you can nudge any that drift.

If the face stays in one spot — a name badge in the corner, or a subject who barely moves — a single static shape with no keyframes covers the entire video.

Step 4: Preview, then export

Play the timeline back and watch the blur stay locked on the face. When it looks right, click Export and choose MP4 or WebM. Blurify re-renders every frame with the blur baked in and encodes the result locally — MP4 export uses ffmpeg.wasm in a background worker so the page stays responsive. Your audio is preserved. The finished file downloads straight to your device, watermark-free.

Blur vs. redact in video — which to use

Blur looks natural and is the right choice for faces in most published video — social clips, vlogs, interviews. Redact (a solid black box) is the safer option when the subject is high-risk — a protected source, a minor in sensitive footage, or anything where you need zero chance of the face being reconstructed. A solid fill leaves no underlying pixels to recover; a light blur on a high-resolution clip sometimes can be partially reversed, so use a strong radius or redact for anything truly sensitive.

A note on free limits

Blurify's free tier covers videos up to 50 MB and 30 seconds, which handles most short clips. For longer or larger videos, a one-time Pro upgrade ($14.99, no subscription) removes the limits. Either way the processing is identical and local — Pro just lifts the size and length caps.

Frequently asked questions

Can I blur a moving face in a video for free?

Yes. Blurify tracks moving faces with keyframes and is free for videos up to 50 MB / 30 seconds, entirely in your browser. Use Detect Faces to auto-generate the tracking keyframes, or set them by hand with the K key.

Does the video get uploaded to a server?

No. The clip is opened locally and processed with the Canvas API and ffmpeg.wasm on your own device. Nothing is transmitted to Blurify or any third party — you can confirm this in your browser's network inspector while exporting. Learn more about how Blurify processes files in your browser.

Will the audio be kept?

Yes. The original audio track is preserved and muxed back with the blurred video on export.

What formats can I export?

MP4 and WebM. MP4 uses ffmpeg.wasm to encode locally for broad compatibility; WebM uses the browser's native recorder.

Can I blur several faces at once?

Yes. Add a separate shape for each face — there's no limit — or let Detect Faces create them all. Each shape keeps its own keyframes so they track independently.

Does it work on a phone?

Yes, in mobile Chrome and Safari, though video export is slower on phone hardware. For long clips a laptop or desktop will be noticeably faster.