Reduce video file size instantly in your browser - no upload needed
Reduce the file size of MP4, MOV, WebM and other videos directly in your browser. Your files stay on your device - nothing is uploaded. Pick a target size for email, WhatsApp or Slack and VidShift handles the rest. Works offline, no signup required.
or click to select a file
🔒 Your files never leave your device - 100% private & secure
VidShift is a completely free online video compressor that runs entirely in your browser. Unlike cloud-based compressors that upload footage to a remote server, VidShift processes every frame locally on your device - your video never leaves your computer or phone. There is no upload queue, no progress bar waiting on a free server slot, and no cloud processing tied to a paid tier. The tool uses WebAssembly and the WebCodecs API to re-encode MP4, MOV, MKV and WebM files directly inside the browser, so you get faster turnaround, total privacy and no file-size caps from an upload endpoint. Works offline after the first visit.
Unlike cloud-based compressors, VidShift runs entirely in your browser - there is no account to create, no server-side queue, and no limit on how many videos you can compress in a day.
Drag your file onto the upload area above or click Select Video. VidShift accepts MP4, MOV, MKV, WebM, OGV and other common formats.
Pick a preset - Email (25 MB), WhatsApp (16 MB) or Slack (100 MB) - or enter a custom target. You can also lower the resolution for an even smaller file.
Hit Compress Video and wait a moment. When it finishes, download your smaller MP4 - ready to send or upload.
Large video files create real problems. Most email providers cap attachments at 25 MB, and platforms like WhatsApp, Discord and Slack enforce their own limits. Uploading oversized clips to social media can be slow or fail entirely. On top of that, uncompressed footage eats through device storage and cloud backup quotas. Compressing a video file lets you share it quickly, meet platform requirements and free up space - without losing the content that matters.
Every time you compress a video, the encoder lowers the bitrate - the amount of data used per second of footage. A lower bitrate means a smaller file, but it also means the encoder has less room to preserve detail. The trade-off is not all-or-nothing, though. Short clips keep much more quality at a given target size because the available data budget is spread over fewer seconds. Downscaling resolution - for example, from 4K to 1080p - is often a better strategy than aggressively lowering bitrate, because the picture still looks sharp on most screens while the file shrinks dramatically. The best approach is to pick the largest target size that meets your needs and experiment with resolution options to find the right balance.
VidShift's video compressor accepts all common video formats. MP4 (H.264 and H.265) is the most widely supported and produces the smallest files at a given quality level - ideal for sharing by email, WhatsApp, or Slack. MOV files from iPhones and cameras are fully supported; VidShift converts them to MP4 during compression. MKV files, commonly used for high-definition content and TV recordings, are supported and compressed to MP4 output. WebM, used by browsers and screen recorders, is also accepted. OGV and other less common formats are handled where your browser's codec support allows.
All output files are delivered as MP4, which plays on every device and is accepted by every major platform. If you need a different output format, use VidShift's video converter after compressing. If you only need the soundtrack rather than the picture, you can convert MP4 to MP3 and extract audio from video in your browser, which produces a far smaller file than any video compression can. And if you want a lightweight looping clip for chat, social or a README rather than a smaller video file, you can convert video to GIF directly in your browser - no upload and no watermark.
The right target size depends on where the video is going. Each platform enforces its own attachment or upload limit, and the smaller that limit, the more the encoder has to lower the bitrate to fit. The table below shows a safe target for the most common destinations - set slightly under each hard limit so the file still fits after the container overhead is added.
| Use case | Platform limit | Suggested target | Best for |
|---|---|---|---|
| Email attachment | 25 MB (Gmail, Outlook) | 23 MB | Clips up to ~2 minutes at 720p |
| 16 MB per video | 15 MB | Short clips up to ~1 minute at 720p | |
| Discord (free) | 8 MB upload | 7 MB | Very short clips at 480p-720p |
| Discord (Nitro) | 50 MB upload | 48 MB | Clips up to ~4 minutes at 1080p |
| Slack | 100 MB shared free limit | 95 MB | Longer clips at 1080p |
| Web / social upload | No hard cap, but speed matters | 30-50 MB | 1080p clips that upload fast and stay sharp |
Most email providers - Gmail, Outlook and iCloud Mail among them - cap attachments at around 25 MB. The Email preset above targets 25 MB in one click; if you want extra headroom for the MP4 container and any email encoding overhead, choose the Custom preset and enter about 23 MB instead. A two-minute clip at 720p fits comfortably at this size with good quality; for anything longer, downscale to 720p if your video is higher resolution (or to 480p if needed), or trim the clip first, so the bitrate stays high enough to look clean. If your video still will not fit, sharing a link from cloud storage is usually a better option than pushing the bitrate so low the picture falls apart.
WhatsApp enforces one of the tightest limits of any messaging app: video messages are capped at 16 MB. The WhatsApp preset above targets 16 MB in one click; if you want a safety margin below the cap, use the Custom preset and enter 15 MB instead. Keep clips to roughly a minute at 720p so the bitrate stays high enough to look clean on a phone screen. When the limit forces the bitrate low, downscaling to 720p or 480p almost always looks better than holding the original resolution at a starved bitrate, because the encoder can spend its limited data budget on fewer pixels. For a longer recording, trimming to just the part you need is the single most effective way to protect quality before you compress.
Discord sets its limit by account tier. Free accounts can upload files up to 8 MB, while Discord Nitro raises the cap to 50 MB (and 500 MB on the highest tier). Target 7 MB for a free account or 48 MB with Nitro to stay safely under the limit after container overhead. The 8 MB free tier is the strictest common limit on the web, so resolution matters more here than anywhere else - drop to 480p or 720p and the encoder can hold detail that a full-resolution clip at the same size would lose. Use the Custom preset above to enter a whole number such as 7 MB, then trim long clips down to the key moment for the best-looking result.
Slack caps uploads on its free workspaces at 100 MB per file, with higher limits on paid plans, making it one of the more forgiving destinations for sharing video. The Slack preset above targets 100 MB in one click; for a small safety margin below the cap, use the Custom preset and enter about 95 MB. At this size a 1080p clip running several minutes keeps plenty of detail, so you rarely need to downscale unless the recording is long - leave the resolution at 1080p and let the higher target carry the bitrate, stepping down to 720p only if a long clip starves it. To share a whole folder of clips at once rather than one file, the bulk video converter applies the same settings across a batch.
Platforms like YouTube, Instagram, TikTok and X do not impose a tight file-size cap, but they re-encode everything you upload - so a smaller, already-clean source uploads faster and survives that second pass better than a huge original. A target of 30-50 MB at 1080p is the sweet spot for most short social clips: small enough to upload quickly on any connection, large enough that the platform's re-encode still looks crisp on a phone screen. Enter a value in this range with the Custom preset. Going much higher rarely improves the final result once the platform has processed it.
File size is bitrate multiplied by duration, so the same target size stretches much further on a short clip than a long one. A 30-second video at 25 MB has roughly four times the bitrate - and four times the detail - of a two-minute video at the same 25 MB. That is why the best results come from picking the largest target your destination allows, then trimming or downscaling rather than accepting a very low bitrate. As a rule of thumb: if a target size forces the bitrate below about 1 Mbps for 1080p footage, step the resolution down to 720p instead and the picture will hold up far better.
VidShift compresses video by re-encoding at a lower bitrate while keeping the resolution you choose. To minimise visible quality loss, select the largest target size that meets your needs. Downscaling resolution - for example, from 4K to 1080p - often gives a bigger size reduction than lowering bitrate alone, and the result still looks sharp on most screens. Because processing runs locally in your browser, you can experiment with different settings without waiting for uploads.
There is no hard limit. The practical limit depends on your device's available memory. Most modern computers handle files up to several gigabytes. For very large files, try lowering the resolution to reduce memory usage during compression.
Select the Email preset (25 MB target) after loading your video. VidShift will automatically calculate the right bitrate to fit your video within the 25 MB limit. For shorter videos, the quality will be higher. For longer videos, you may want to also lower the resolution for best results.
Select the WhatsApp preset (16 MB target). WhatsApp has a 16 MB file size limit for video messages. VidShift will calculate the optimal bitrate to fit within that limit. For longer videos, trimming to just the part you need with the video trimmer is another effective way to reduce file size before compressing.
Some quality reduction is expected whenever you compress a video - that is how compression works. VidShift calculates the best bitrate for your chosen target size and video duration, so shorter clips keep more detail. To get the best balance of size and quality, pick the largest preset that fits your needs and consider lowering the resolution one step rather than accepting a very low bitrate. All processing happens on your device, so you can try multiple settings quickly.
It depends on your device and the video's length and resolution. Short clips typically compress in seconds; longer or higher-resolution videos may take a few minutes. A progress bar and estimated time remaining are shown throughout. Because VidShift runs entirely in your browser using WebAssembly, performance scales with your hardware - modern laptops and desktops handle most files quickly, and hardware acceleration is used when available.
Yes. Your video never leaves your device. VidShift has no backend servers that receive or store your files. All compression runs locally in your browser using WebAssembly, ensuring complete privacy. The tool even works offline after your first visit.
VidShift supports all common video formats: MP4, MOV (including Apple ProRes), MKV, WebM, OGV, M4V, and MPEG-TS. The compressed output is always saved as MP4 for maximum compatibility across devices and platforms.
Yes. When the compression finishes, the "Ready to do more?" links hand your result straight to the next tool - trim it, add a watermark, change its speed and so on - with no download-and-re-upload step in between. The file is handed over through your browser's own local storage and never touches a server, so chaining tools together stays exactly as private as a single conversion.
Yes. VidShift works in any modern mobile browser - Chrome, Safari, Edge or Firefox. Open this page in your mobile browser, select your video and choose a target size. The compression runs on your phone's processor and your video file isn’t uploaded or processed on our servers. For large or high-resolution files, a recent phone will give the best experience.
Completely free, with no hidden limits. There is no file size cap, no watermark, no daily quota and no account required. VidShift processes your videos directly in your browser, so your files are never uploaded and we don't pay for server-side media processing or storage. This keeps our costs low and lets us offer the tool for free. You can compress as many videos as you like.
Yes. VidShift is a completely free video compressor that never adds watermarks, logos or branding to your output. There are no daily limits, no signup and no hidden paywalls. Because the tool runs entirely in your browser, there are no server costs - so we can offer it for free without the compromises other services make.
Open VidShift in any modern browser - Chrome, Edge, Safari or Firefox. Drop your video onto the page, choose a target size and click Compress Video. The entire process runs locally in your browser using WebAssembly, so there is nothing to download or install. Your video is never uploaded to a server, and the tool even works offline after your first visit.
The most effective approach combines two strategies. First, choose the largest target size that fits your needs - this preserves the most detail. Second, consider lowering the resolution by one step (for example, 4K to 1080p or 1080p to 720p). Downscaling removes pixels the viewer rarely notices on smaller screens, while giving the encoder far more headroom for the remaining detail. If your video is longer than necessary, trimming it before compressing is another easy way to cut file size without touching quality.
Drop your 4K video onto the page and select a target size or resolution. The most effective way to compress 4K footage is to downscale the resolution - for example, to 1080p - rather than aggressively lowering the bitrate at full 4K. A 1080p output looks sharp on virtually every screen and is dramatically smaller than the 4K source. Use the resolution dropdown to select 1080p or 720p, then set a target size to control the bitrate further.
VidShift compresses video by re-encoding at a lower bitrate or resolution - this is what actually reduces the file size. True compression without re-encoding (remuxing) does not reduce file size; it only changes the container format. If you want to reduce file size, re-encoding is necessary. VidShift's processing runs entirely in your browser, so you can re-encode without uploading your file anywhere.
Discord limits file uploads to 8 MB on free accounts and 50 MB with Nitro. After loading your video, enter a custom target size of 7 MB (to leave a small margin below the 8 MB limit). VidShift will calculate the right bitrate automatically. If the result looks too compressed, try lowering the resolution to 720p or 480p first - this often gives a better-looking result at a small file size than keeping the original resolution with a very low bitrate.
For Instagram and TikTok, set the output to MP4 with a resolution of 1080p or lower and a target size around 30-50 MB - this compresses the video enough to upload quickly while keeping it crisp on a phone screen. Both apps re-encode anything you upload, so starting from a well-compressed source gives a cleaner final result than uploading a giant original. Trim the clip with the video trimmer first if it's longer than the platform allows.
On either macOS or Windows you can compress a video by opening VidShift in Chrome, Edge, Firefox or Safari - no separate software is needed. Drag your file onto the page, pick a target size or quality preset, then click Compress Video. The smaller file saves straight to your Downloads folder, with the original left untouched on disk.
To compress multiple videos at once, use the bulk video converter, which applies the same compression settings to every file in a batch. Each video is processed in your browser one after the other and the results download as a ZIP, so you can shrink a whole folder of clips without re-selecting settings each time.