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Why Shiklo Tools?
Simple, private tools that just work — right in your browser.
- Private Everything runs in your browser. Files are never uploaded.
- Secure Encrypted HTTPS connection, and nothing you open is stored on our servers.
- No login required No account, no sign-up, no email. Just open a tool and use it.
- Fast No upload or download wait — results appear instantly.
- Free All tools are free to use, with no limits.
- Works everywhere Phone, tablet or computer, in any modern browser.
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Frequently asked questions
Are my files or text uploaded anywhere?
No. Every tool runs inside your browser on your own device. Nothing you enter or open is sent to a server.
Do I need to create an account or log in?
No login is required. There are no accounts — open any tool and start using it straight away.
Are the tools really free?
Yes. All tools are free, with no limits or watermarks. The site is supported by ads.
Does it work on my phone?
Yes. The tools work in any modern browser on phones, tablets and computers.
Can I use the tools offline?
Once a tool has loaded it does its work on your device, so it keeps working even if your connection drops.
Which file types are supported?
PDF, Word, Excel, PowerPoint, OpenDocument and RTF documents, JPG, PNG, WebP, HEIC, AVIF, GIF and BMP images, MP4, MOV, WebM and MKV videos, MP3, WAV, M4A, OGG and FLAC audio, ZIP, 7z, RAR, TAR and GZIP archives, CSV, JSON, XML and plain text. Each tool lists exactly what it opens.
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Video Converter
Convert videos between MP4, WebM, MOV and MKV in your browser — fast without quality loss when possible, or re-encoded for best compatibility.
Change a video's format without installing software: MOV from an iPhone or camera to MP4 for Windows and the web, WebM screen recordings to MP4 for editing or sharing, MKV files to MP4 for your TV or phone, or MP4 to WebM for a website. The Video Converter reads MP4, M4V, MOV, WebM and MKV files and writes MP4, WebM, MOV or MKV.
In Fast mode it keeps the existing video and sound streams whenever the new format can hold them, so the conversion is a quick repackaging (a remux) that takes seconds and loses no quality; only what the new format can't hold is re-encoded. Most compatible mode re-encodes to the codecs every player supports for that format. The conversion runs in your browser — your video is never uploaded.
How to use Video Converter
- Choose or drop a video.
- Choose the format: MP4, WebM, MOV or MKV.
- Choose Fast (keep quality) or Most compatible.
- Press Convert and download the new file.
Features
- MP4, M4V, MOV, WebM and MKV in; MP4, WebM, MOV and MKV out.
- Fast mode: repackages without re-encoding when possible.
- Most compatible mode: H.264 / AAC, or VP9 / Opus for WebM.
- Shows the codecs of your video before converting.
- Progress and Cancel for long videos.
- Runs in your browser with WebCodecs: no upload, no watermark.
Formats and codecs explained
A video file is a container (the format, like MP4) holding a video stream and a sound stream compressed with codecs (like H.264 and AAC). Changing the container is fast; changing the codec means re-encoding. The table shows what each format is best for and the codecs Most compatible mode uses.
| Format | Best for | Codecs (Most compatible) |
|---|---|---|
| MP4 | Everything: phones, Windows, Mac, TVs, social networks, editors | H.264 video, AAC sound |
| WebM | Websites and browsers; open, royalty-free | VP9 video, Opus sound |
| MOV | Apple apps such as iMovie and Final Cut | H.264 video, AAC sound |
| MKV | Media players and archiving; holds almost any codec | H.264 video, AAC sound |
Common conversions
MOV to MP4: iPhone and many cameras record H.264 or H.265 in MOV files, which MP4 can hold too, so Fast mode just repackages them. WebM to MP4: WebM uses VP8 or VP9 with Opus; for the widest support choose Most compatible to get H.264 and AAC. MKV to MP4: MKV often already contains H.264 and AAC, which Fast mode keeps. MP4 to WebM: WebM can't hold H.264, so the picture is always re-encoded to a WebM codec (VP9 in Most compatible mode).
Fast or most compatible?
Start with Fast: it is quickest and keeps the original quality. If the converted file doesn't play on the device you need — some older TVs and players don't support H.265 or VP9 — convert again with Most compatible, which produces H.264 and AAC in MP4, MOV and MKV, or VP9 and Opus in WebM. Re-encoding takes longer and changes the quality slightly, so only use it when needed. To make a file smaller at the same time, use the Video Compressor instead.
Private conversion in your browser
Online converters upload your video to their servers and often limit the file size or add a watermark. This converter reads the file directly from your device and converts it with your browser's WebCodecs media engine, which uses your device's hardware encoder where available. Nothing is uploaded, there are no limits beyond your device's memory (files up to 2 GB can be opened), and the result is yours alone. Each file is checked by its content, so a renamed file is refused with a clear message.
Frequently asked questions
How do I convert MOV to MP4?
Open the MOV file, choose MP4 and Fast mode, and press Convert. Most iPhone MOV files are converted in seconds without quality loss.
How do I convert WebM to MP4?
Open the WebM file, choose MP4 and Most compatible for H.264 video that plays everywhere.
Does converting reduce quality?
Not in Fast mode when the streams can be kept. Re-encoding changes the quality slightly.
Is my video uploaded?
No. The conversion runs in your browser and the video stays on your device.
Which format should I choose?
MP4 for almost everything. WebM for websites, MOV for Apple editing apps, MKV for media players.
Why does my iPhone video show an HEVC message?
H.265 (HEVC) can only be read where the browser supports it: Safari, or Windows with Microsoft's HEVC Video Extensions.
Can I convert video to MP3?
Yes, with the MP4 to MP3 tool, which saves just the sound.
Related tools
Video CompressorReduce the size of MP4, MOV and WebM videos in your browser: pick a quality or a target size like 25 MB, lower the resolution, keep the sound.
Video TrimmerTrim a video to a start and end time in your browser — instantly without re-encoding, or frame-exact. MP4, MOV, WebM and MKV. No upload.
Video ResizerResize a video to 1080p, 720p, 480p or an exact size, or reshape it for Reels, Shorts, TikTok (9:16), square (1:1) and 4:5 with bars or crop.
MP4 to MP3Convert MP4, MOV and WebM videos to MP3 or M4A audio in your browser: choose the quality, cut a part, convert several files. No upload.
Video to GIFTurn a part of an MP4, MOV or WebM video into an animated GIF in your browser: pick start and end, frame rate, width and colours. No upload.
Audio ConverterConvert audio between MP3, M4A (AAC), OGG (Opus) and WAV — from MP3, WAV, M4A, OGG, Opus and FLAC — one file or many, in your browser.