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How to Watermark a Video — Channel Name or Logo, WYSIWYG
Stamp a copyright line or logo onto a video before sharing it. Position (9 spots), size and opacity adjust with a live preview, and the video is never uploaded.
How to Make a YouTube Thumbnail from Your Video — No Design App Needed
Pause on the best frame of your video, capture it, add a title, and save a 1280×720 thumbnail. Style presets give it structure even without design skills.
How to Merge Audio Files into One — Even with Mixed Formats
Join split voice memos or lecture recordings into a single MP3, in the order you choose. Mixed formats and sample rates are matched automatically, inside your browser.
How to Add Background Music to a Video — Loop, Volume, Fade
Lay music over a silent vlog or timelapse. Short tracks loop automatically to fill the video, and you choose whether to mix with or replace the original sound.
How to Trim a Video — Keep Just the Part You Need (No Quality Loss, Seconds)
Cut the section you need out of a long video. 'Fast' finishes in seconds with zero quality loss; 'Precise' cuts frame-accurately. The video never leaves your device.
How to Reduce Video File Size — Even to an Exact 25MB (In Your Browser)
Practical ways to shrink large videos that keep hitting messenger, email, and upload limits — re-encoded inside your browser, with an honest note on big files.
How to Make a Karaoke Track (Remove Vocals from a Song) with AI, in Your Browser
Make a backing track for karaoke practice or covers. An AI source-separation model runs inside your browser — no upload — and you get the isolated vocals too.
How to Play a Video with SMI or SRT Subtitles (Without Broken Korean Text)
Got a video and a separate SMI/SRT subtitle file? Overlay them in a browser player — it auto-detects the legacy EUC-KR encoding common in Korean SMI files, and lets you nudge sync in 0.5s steps.