Free Audio & Video Tools

6 browser-based media tools — trim, record, convert subtitles and plan bitrates

Media work usually means heavyweight software, but a surprising share of everyday audio and video tasks are small: cut the first ten seconds off a recording, convert a subtitle file, figure out what bitrate fits on a memory card. The tools in this category handle those jobs in the browser, no installation required.

Your media files are processed locally — trimming and conversion happen on your device, so recordings, footage and transcripts are never uploaded. That makes these tools usable even for unreleased and confidential material.

Browser media processing has quietly become powerful: the Web Audio API can decode, edit and re-encode sound, and modern JavaScript handles video containers well enough to trim without re-encoding. That's what these tools build on — which is why a laptop from a few years ago handles them fine, and why there's no server queue, credit system or upload limit involved. For color grading and multi-track editing you'll still open a real editor; for the quick cut, the format hop and the planning math, this page is faster.

All Audio & Video Tools at a Glance

What Each Tool Does

Every tool below opens instantly, needs no account, and processes your data locally in your browser. Here is what each one is for:

Audio Toolbox

Record from your microphone and convert audio between formats — a small studio for voice memos and quick captures. Open the Audio Toolbox →

Audio Trimmer

Cut precise clips out of audio files with a visual waveform — trim podcasts, ringtones and voice notes in seconds. Open the Audio Trimmer →

Video Trimmer

Trim video clips to exact start and end points and export straight from the browser. Open the Video Trimmer →

SRT ⇄ VTT Converter

Convert subtitle files between SRT and WebVTT in both directions, with automatic format detection and clean handling of styling tags. Open the SRT ⇄ VTT Converter →

Bitrate Calculator

Solve for bitrate, file size or recording duration — the media planning math, done instantly and correctly. Open the Bitrate Calculator →

How to Choose the Right Tool

The Audio Trimmer cuts clips out of audio files with waveform precision, and the Video Trimmer does the same for video — both export directly from your browser. The Audio Toolbox bundles recording and format conversion for voice memos and quick captures. The SRT ⇄ VTT Converter switches subtitle files between the two standard formats in either direction, with automatic detection. And the Bitrate Calculator connects file size, duration and bitrate, answering the planning questions every recording and stream starts with.

Frequently Asked Questions

Are my audio and video files uploaded?

No — trimming, recording and conversion all run locally in your browser. Files never leave your device.

What file formats do the trimmers support?

Common browser-supported formats: MP3, WAV, OGG and M4A for audio; MP4 and WebM for video. Output options are shown in each tool.

Is there a length or size limit for trimming?

No fixed limit — very large files depend on your device's memory, since processing is local.

Can I convert subtitles from YouTube or Zoom?

Yes — both export WebVTT, which the SRT ⇄ VTT Converter turns into SRT for video editors (and back).

Explore More WiserWork Categories

WiserWork offers 295 free browser-based tools across 22 categories — all private, all free, no sign-up required.