Video Slow Motion is a single-page tool for the common video editing and conversion task it is named after. Slow any video down to between 10% and 100% of its original speed. Audio pitch is preserved using FFmpeg's atempo filter. Files are processed entirely in your browser with FFmpeg WebAssembly. The interface keeps the input on one side, the configurable options in the middle, and the result on the other side. Most jobs start and finish without any scrolling.
Video Slow Motion fits naturally into the workflow of teams compressing demo recordings and product teams shipping release demos, both of whom typically need a fast result inside the browser. There is no learning curve to budget for: anyone who has used a typical web upload form can complete a run on the first try.
The right moment to reach for Video Slow Motion is when you have a focused video editing and conversion job that fits inside a browser tab. Open the page, drop in the file or paste your input, choose the options that matter, and the tool returns the result.
Internally the tool runs on FFmpeg compiled to WebAssembly — the same processing stack used by professional desktop pipelines, just compiled for the browser. MP4, WebM, MOV, MKV, AVI, FLV, and OGV files are accepted natively. 500 MB is the practical ceiling, set so the tool stays responsive on phones and older laptops.
The architecture is local-first by design. Once the page is loaded, you can disconnect from the network and the tool still completes the job. The processing stack — FFmpeg compiled to WebAssembly and the small UI shell wrapping it — ships with the page itself, so the tool keeps working in offline conditions, on a captive-portal Wi-Fi, or behind a corporate proxy that limits what the tab can reach.
Once you have used Video Slow Motion, the natural next steps depend on what you are doing with the result. Common follow-ups include Video Speed Changer, Video Stabilizer, and Video Converter. These are surfaced on the page so you do not have to hunt the catalog manually.
On limits: 500 MB per file is the ceiling. Output formats and quality settings are listed in the controls panel above, and they apply to every run.
Video Slow Motion is honest about scope: it handles a single, well-defined video editing and conversion step. Specialist edge-case work — uncommon formats, very large inputs, or pipelines that need scripting — is what dedicated desktop apps are for. This page handles the common case quickly.
Output handling is intentionally boring: Video Slow Motion produces `{name}-edited.{ext}` and triggers your browser's standard "save" behaviour. If you have a default download folder configured, that is where it will land. There is no Favtoo-side history of jobs you have run.
Video Slow Motion is structured around the idea that a useful tool should be its own page. Open the page, do the work, close the tab — the page is the entire product. There is no onboarding flow because there is nothing to onboard into.
Video Slow Motion fits the gap where opening a desktop app feels heavy and writing a script feels overkill. The page handles the common video editing and conversion task with sensible defaults so a single visit usually completes the job; for highly specialised work, a dedicated desktop application can offer more knobs to turn.
Tips from users who reach for Video Slow Motion regularly: process one input first to confirm the settings produce what you expect before committing to a batch; treat the page as the working surface and avoid leaving large jobs running in a backgrounded tab where the browser may throttle JavaScript; and if a particular file fails, check whether the source is intact by opening it in its native viewer — most "tool errors" are actually input errors.
If the result is not what you expected, the most common causes are easy to check. Confirm the input is under the 500 MB ceiling — files just above the cap fail silently because the engine refuses to allocate the buffer. Confirm the input is one of the supported formats. And if the page itself feels slow, try closing other heavy tabs to free up memory; the engine runs in your browser, so it competes for the same resources as everything else open.
That is the whole tool. Use Video Slow Motion for as long as it stays useful to you, and if it does, the catalog has many more tools built the same way. Each applies the same single-purpose discipline, so the way you used this page transfers to the next one you try.
A WebAssembly build of FFmpeg loads in this page and applies `setpts` to slow down the video frames and a chain of `atempo` filters to slow the audio while preserving its pitch — entirely on your device.
Server tools use multi-threaded native FFmpeg with hardware encoders. WebAssembly is single-threaded inside the browser, typically 4–8× slower for re-encoding. The trade-off is total privacy: your video never leaves your device.
It depends on your source frame rate. Slowing 60fps to 0.5× plays at an effective 30fps which looks smooth. Slowing 30fps to 0.5× plays at 15fps which looks choppier. For super-smooth slow motion, record at 60fps or higher first.
No — audio pitch is preserved using FFmpeg's atempo filter, which slows playback while keeping voices and music at their natural pitch. Without this it would sound underwater-deep.
10% (0.1×) is the minimum — your 30s clip becomes a 5-minute clip. Most cinematic slow-mo lives between 0.25× and 0.5×.
Video Speed Changer is a general speed tool that handles both slowing and speeding up. This tool is purpose-built for slow motion with the pitch-preservation defaults that look and sound best for that use case.
Up to 500MB. Slow motion expands duration, so 4× slowed output of a 100MB source can produce a 400MB+ file.
No. The slow motion runs entirely in your browser tab. Nothing is transmitted, stored, or logged. Closing the tab erases the file from memory immediately.
Video Slow Motion works in any modern browser released in the last few years — Chrome, Edge, Firefox, Safari, Brave, Arc and the major Chromium derivatives are all supported. The underlying engine relies on widely-supported web APIs, so there is nothing exotic to install. If you are on a very old browser version and the tool fails to load, updating to the latest release of your preferred browser is the only fix needed.
Video Slow Motion is updated whenever the underlying engine releases an improvement or a bug fix. Because the tool is delivered as a static page, every visit fetches the latest version automatically — there is no "version" to manage on your end. If a particular release ever changes default behaviour, the change is documented on Favtoo's changelog so you can confirm what shifted.
Favtoo keeps no copy of your file because Favtoo never receives your file. Video Slow Motion runs entirely in your browser, the input is held only in your tab's memory, and closing the tab discards it. There is no opt-in cloud history, no "recent jobs" panel synced to an account, and no server-side retention to configure — the architecture simply has nowhere for your file to be stored.
Your file is processed inside your browser by FFmpeg compiled to WebAssembly. The engine reads the file's bytes from your tab's memory, computes the result, and writes the result back into the tab. You can confirm what the page does by opening developer tools and watching the Network tab during a run — the requests you see are for the tool's static assets only.
Inputs are capped at 500 MB per file, which keeps memory usage stable across phones, tablets and older laptops. You can run Video Slow Motion as often as you need; every run produces a full-quality result.
Video Slow Motion uses native HTML controls wherever possible, which means keyboard navigation, focus rings, and screen-reader labels work the way the platform expects. The drop zone accepts files via the keyboard-accessible file picker as well as drag-and-drop, and result downloads use standard browser download flows. If you spot an accessibility gap, Favtoo treats it as a bug worth fixing.
Video Slow Motion accepts MP4, WebM, MOV, MKV, AVI, FLV, and OGV. If your input is in a format that is not directly supported, convert it first using one of Favtoo's converter tools — every Favtoo converter outputs a file that is a clean input to the next tool in the chain.
Video Slow Motion processes one input at a time by design — it keeps memory usage predictable on lower-end devices and makes results easier to verify. To handle a folder, run the tool once per file; the page stays loaded between runs and remembers your last-used settings, so the second run is essentially instant.
Video to GIF
Convert any video clip to an animated GIF entirely in your browser. Pick the start, length, frame rate, and width — your file is processed locally with FFmpeg WebAssembly and never uploaded.
Screen Recorder
Record your screen, a window, or a browser tab directly in your browser. Optionally include system audio and your microphone. Capture, preview, and download the video without installing any app — and without uploading anything.
Webcam Recorder
Record your webcam directly in your browser with optional microphone audio. Pick the resolution (480p, 720p, or 1080p), frame rate, and mirror mode, then capture and download the result without installing any app.
Screen + Webcam Recorder
Record your screen with your webcam composited into a picture-in-picture corner — perfect for tutorials, course videos, demos, and reaction recordings. Pick the camera position, size, and audio sources, then capture and download in your browser.
Video Slideshow Maker
Turn a stack of photos into an MP4 slideshow with per-slide durations, crossfades, and an optional soundtrack. Pick the resolution (up to 1080p), frame rate, and transitions, then download a single MP4 — all processed in your browser with FFmpeg WebAssembly.
Video from Images + Audio
Combine a stack of photos with a music track or narration into a single MP4 video. Pick the resolution, per-slide duration, transitions, and let the slideshow length match the audio. All processed in your browser with FFmpeg WebAssembly.
Video Trimmer
Set precise in and out timestamps, snap to keyframes when needed, and document handles for social-safe cutdowns.
Video Splitter
Split any video into 2–10 equal-length pieces, packaged as a downloadable ZIP. Files are processed entirely in your browser with FFmpeg WebAssembly using lossless stream-copy.