Microphone, camera, screen and files are read by your browser, and recordings and converted files stay in this tab until you download them.
These tools check the hardware a video call, a game or a recording depends on, record what you need, and convert audio and video, all inside your browser tab. Nothing is uploaded: the microphone, camera and screen are read by your browser, and a recording or converted file stays in this tab's memory until you download it or close the page.
Before a call or an interview, Mic Test shows a live input level and lets you record 5 seconds and play it back, and Webcam Test shows the picture with the resolution and frame rate the camera actually delivers. To record, Voice Recorder saves audio from your microphone and Screen Recorder captures a tab, a window or the whole screen on a computer, with tab or system audio where the browser offers it. The file type is whatever your browser records, usually WebM, and the page names it.
To check a device, Keyboard Tester lights up each key you press and shows how many keys register at once, Dead Pixel Test fills the screen with solid colours so a stuck or dead pixel stands out, Screen Resolution Checker reports the screen and window size and the pixel ratio, and CPS Test counts clicks per second over 1 to 60 seconds. Reaction Time Test gives your average over five tries in milliseconds. Your browser asks for permission before any page uses the microphone, camera or screen, and only when you press Start.
To convert and edit audio, Video to MP3 pulls the sound out of an MP4, MOV, WebM or MKV video, Audio Converter turns WAV, M4A, OGG, FLAC or MP3 into MP3 or WAV, MP3 Cutter saves the part you pick on the waveform with an optional fade, Audio Joiner puts 2 to 20 files in order with an optional crossfade, and Video to GIF saves up to 15 seconds of an MP4, MOV or WebM video as an animated GIF. These use your browser's own decoder, so the formats that open depend on the browser. For practice, Metronome runs from 20 to 300 BPM with tap tempo, and Guitar Tuner listens to a string and shows its note and how many cents sharp or flat it is.
No. Mic Test and Webcam Test show a live signal inside this tab, and the 5-second test clip in Mic Test stays in memory. Nothing is sent to a server. Closing the tab stops the device and discards the clip.
Browsers never let a page use the microphone, camera or screen without asking, and they ask separately for each of the 3. The request appears only after you press Start. If you pressed Block, allow the device again from the icon at the left of the address bar, then press Start once more. Most browsers remember your choice for 1 site at a time.
Whatever your browser's recorder produces: Chrome, Edge and Firefox usually record WebM, and Safari records MP4. The page shows the real type before you download, for example a 2 minute voice note as a WebM audio file.
Usually not. Screen capture from a web page needs the browser's screen-sharing feature, which most phone browsers do not offer. Screen Recorder needs just 1 thing from the browser, screen sharing, and says so when it is missing. Mic Test, Webcam Test, Voice Recorder and CPS Test work on phones.
Open Video to MP3, add the MP4, choose a bitrate such as 192 kbps and press Extract audio. A 3-minute video gives about 4.1 MB at 192 kbps. The tool offers 128, 192, 256 and 320 kbps, or variable quality, and nothing is uploaded.
The converters use your browser's own decoder, so they only open formats the browser can play. An OGG or Opus file may fail in Safari, and MKV or AC-3 audio may fail in some browsers. A file without an audio track fails everywhere. Try Chrome, Edge or Firefox, or an MP4 or MOV with AAC audio.