HermitFile Pro

Remove background noise from a recording

Learns your clip's own background hiss, hum or rumble from a quiet stretch of it, then subtracts that specific sound from the whole track. Runs entirely on this device. Works on video or audio-only files, and the picture is copied across untouched when there is one.

Drop a video or audio file hereTap anywhere in this box
MP4, MOV, MKV, WebM, MP3, M4A, WAV — anything your browser can read, with an audio track. Any length: there is no upload, so there is no limit.

Nothing is uploaded. Open your browser’s Network tab while you convert — you will see the file go nowhere.

Noise settings

What you'll get back

Worked out from this actual file and this actual browser, before anything is written.

Your cleaned file

It learns from your recording, not a generic filter

A lot of "remove background noise" tools apply one fixed filter to everything, which is why they either barely help or scrub away part of the voice along with the hiss. This one finds a genuinely quiet moment in your own clip — a pause, room tone before anyone speaks — and learns exactly what the background sounds like there, broken down by frequency. Every recording's noise is a little different (a fan hums at a different pitch than traffic), and this listens to yours specifically before doing anything to it.

Strength, and when to back it off

Higher strength subtracts more of the learned noise at every frequency; lower strength is gentler and leaves more of a floor under quiet parts. Very aggressive settings on a difficult recording can start to sound thin or slightly underwater — that's the sign to lower the slider. Nothing is written until you press Convert, so there's no cost to trying a setting and changing your mind.

Why the file type can change

Cleaning the audio is real signal processing, so the sound is genuinely re-encoded — there's no wrapper trick for that the way there is for a straight copy. The video, if there is one, doesn't need to be touched at all, so it's copied across as compressed packets exactly like mov-to-mp4 and the site's other video tools do, provided its codec fits in a container this browser can also put the cleaned audio into. Both are checked against this actual browser before you convert anything, and the plan says exactly what will happen to each track.

Nothing is uploaded

Decoding the audio, learning the noise profile, cleaning the track and copying the video all happen in this page. There is no server here to send the file to, and the page's security policy blocks any connection to anywhere but this site. Here is how that is enforced.

How to remove background noise from a recording

  1. Drop the video or audio file in. Nothing is sent anywhere — the whole file stays on this device.
  2. It finds the quietest stretch automatically and shows you what it learned before doing anything.
  3. Set the strength, press Convert, and download the cleaned file.

All 39 HermitFile tools

Every one of them runs in your browser. Nothing you open is uploaded, and nothing is stored.

Show all tools

Image tools

Make a passport photoFinds the face and frames it to a passport specification, then saves at the exact pixel size and under the KB limit. Check my passport photoCheck a passport or visa photo against the rules the authority actually publishes, before you submit it. Check my document uploadCheck a document against a portal’s published format list and size ceiling, before it is silently rejected. Resize to an exact KBHit a pixel size and a KB limit at the same time, without the picture being shrunk behind your back. Crop & rotateCut an exact rectangle by dragging or by typing the numbers. Rotate, flip, and never enlarge. iPhone HEIC to JPGConvert iPhone photos into a format every upload form accepts. Convert formatWebP, AVIF, PNG, JPG and more. Transparency gets the colour you choose instead of turning black. Compress an imageMake the file smaller while the picture stays exactly the same width and height. Clean a fileSee what a file says about you, then remove it — including text under a redaction box. View & remove EXIFSee the camera, timestamp and GPS coordinates hidden in a photo, then save a clean copy. QR code generator & readerEncodes exactly the link you type, with no redirect through anyone else’s domain. Reads codes from an image too. Read text from a scanPull selectable text out of a scanned PDF or a photo of a page, without the scan leaving your device.

Video tools

MOV to MP4Turn an iPhone .mov into an .mp4 by swapping the wrapper, with the video copied across and nothing re-encoded. Trim a videoKeep the part you want. The clip is copied rather than re-encoded, so no quality is lost. Split into partsCut a long recording into pieces short enough to post, without re-encoding any of them. Rotate a videoChange the rotation flag a phone wrote instead of re-encoding the picture. Seconds, not minutes. Remove the soundDrop the audio track and copy every frame across untouched — same quality, same size. Video to MP3Convert a video’s sound to MP3, or lift the original audio out byte for byte with nothing re-encoded. Video to GIFPick a range, a frame rate and a size, and get an animated GIF back with nothing uploaded. Green screen swapSwap a green or blue screen for a solid colour with a live preview, no AI model and no watermark. Silence removerFinds the quiet stretches by listening to the audio and cuts them out, with a timeline showing every cut first. Blur pad to a new ratioFit a video into 9:16, 1:1 or another shape with a blurred background instead of black bars. Compress a videoAim at a Discord, email or WhatsApp limit — or your own — and get an MP4 checked afterwards, not just promised. Noise removerLearns your recording’s own background hiss or hum from a quiet stretch, then subtracts exactly that. Auto-reframeCrops a landscape clip to a new shape and pans the crop to follow the motion, instead of a fixed centre. CaptionsBurns an .srt or .vtt subtitle file into the video as styled, timed on-screen text. Beat syncFinds the beats in the clip's own audio and lands a flash or a zoom-punch on each one. Highlight finderScores a clip by loudness and movement, and ranks the best stretches to cut out, losslessly.

PDF tools

Merge PDFsJoin several PDFs into one, in the order you choose, and rotate pages losslessly. Split PDFPull out a page range, or break a document into one file per page. Compress a PDFShrink the pictures inside the file and leave the text selectable. Refuses to hand back a bigger file. PDF to imagesRender each page to a JPG or PNG at the resolution you choose. PDF to textPull the words out of a PDF and copy them or save a .txt file. Says so when a PDF is a scan. Remove a PDF passwordSave a copy that opens with no password, using the password you already know. Rotate PDF pagesTurn some pages or all of them, permanently, with no loss of quality. Remove PDF pagesName the pages you want gone and get everything else back as one document. Redact a PDFSearch every page for a name or a number, remove the text itself, then check the finished file. Images to PDFCombine photos into one PDF that lands under the KB limit the portal demands. Bank statement to CSVEvery transaction out of a statement PDF as a spreadsheet, and it checks its own total against the closing balance.