Audio & Video Tools
Trim, speed up, boost and convert audio with the browser's own audio engine. Voice memos and meeting recordings are audio of people, the reason these tools process everything on your device and work with the internet disconnected.
- Audio Trimmer Cut the exact seconds you need from any audio file, preview the result and download, without the recording leaving your device.
- Audio Speed Changer Play back a lecture at 1.5× permanently, or slow a riff to 0.75× to learn it, rendered on your device and saved as WAV.
- Audio Volume Changer Make a quiet recording louder (or a loud one quieter), with the tool measuring your file's headroom so you boost without distortion.
- Audio to WAV Converter Any audio your browser plays → standard 16-bit WAV, the format every editor, sampler and legacy system accepts, converted on your device.
- Video Frame Extractor Pull a still image out of a video: scrub to the moment you want, then capture it at the video’s full resolution as PNG or JPEG. Nothing leaves your device.
- Audio Merger (Join Audio Files) Combine several audio clips end to end: add your files, drag them into order, and download one merged WAV, all processed locally in your browser.
- SRT to VTT Converter Turn an .srt subtitle file into the .vtt format HTML5 <track> needs, paste or load the file, all locally.
- VTT to SRT Converter Turn a .vtt caption file into the widely-supported .srt format, paste or load it, all in the browser.
- Subtitle Shifter (Resync) Captions running early or late? Shift every cue by a set number of seconds to resync, SRT or VTT, all locally.
- WAV / AIFF Audio Inspector Drop a .wav or .aiff file to instantly read its sample rate, bit depth, channel count, codec and length, straight from the file header.
- MP3 Tag Reader (ID3) Drop an .mp3 to read its ID3 tags (title, artist, album, genre…) and audio details like bitrate, sample rate and length, all locally.
- FLAC Metadata Viewer Drop a .flac file to read its audio specs (sample rate, bit depth, duration) and its Vorbis comment tags, title, artist, album and more.
Trim and adjust audio in the browser
These tools handle common audio jobs, trimming a clip, converting between formats, and adjusting volume, using the browser's own Web Audio processing, so your recording is worked on locally and never uploaded. That keeps voice memos, interview audio and music drafts private, and it means there's no queue and no file-size limit imposed by a server.
Load a file, make your edit, and export, all on your device, offline once the page has loaded. (Full video transcoding via ffmpeg.wasm is on the roadmap.)
Frequently asked questions
How do audio tools work without a server?
Browsers include the Web Audio API: native decoders for MP3, WAV, OGG, M4A and FLAC plus an offline renderer for processing. Trimming, speed and gain changes run as sample math on your device, recordings never leave your browser.
Why do all the tools output WAV?
Browsers can decode compressed audio but don't reliably encode it. WAV is uncompressed, lossless and universally supported, and converting it to MP3 later in any converter or editor costs exactly the same quality as encoding directly would have.
Where are the video tools?
Video re-encoding needs full codec suites that browsers don't expose for writing, so honest client-side video tools require heavyweight WebAssembly builds. We're evaluating that for a future release rather than shipping a fake "uploader" version. The audio side is fully live.