It is created by the same people that created the online DAW Audiotool and no you do not have to register or anything like that.
Here is what they have to say about it:
Audiotool Launches Free Online Sample Editor
Our FREE Online HTML Sample Editor is here now! We officially launch it today and it’s called Probe. Probe offers a variety of features such as industrial standard waveform-rendering, fast multi-threaded effects and unlimited history steps. Probe is running on all modern browsers as Chrome, Firefox, Opera and Edge. Probe exports to lossless wav-format (16 or 32bit). Drum-loops can be easily sliced with the Beat-Grid feature and a metronome. With a minimalistic, nice looking, responsive user-interface and lots of keyboard-shortcuts, Probe offers an easy to operate sample-editing platform right in your browser.
Audiotool users can export samples directly into the audiotool cloud, however, Probe can also be used by anyone who’s not registered with audiotool.
Probe is in line with our mission to democratise the process of music creation and collaboration in the cloud. Like all of our products within our browser-based audio workstation, it is web-based and free to use.
With nearly 1M users from around the world now, we’re really excited about launching our first new product in a while. Probe already runs on the latest technology we are developing for the next version of audiotool which we’re continuously working on. Stay tuned!
Probe can be reached via this link: https://probe.audiotool.com
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