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Local multi-file conversion & processing

MP3 compressor

Shrink MP3 files locally by re-encoding at a lower bitrate. Voice notes and podcasts fit anywhere.

File converter

0 files

Every file. A new possibility.

Images, audio, documents and video. Pick your files and give them a new format.

or drop your files here
Supported formats

Images

.png, .jpeg, .jpg, .webp, .gif, .svg, .jxl, .avif, .heic*, .heif*, .ico, .bmp, .cur, .ani*, .icns*, .nef*, .cr2*, .hdr, .jpe, .mat, .pbm, .pfm, .pgm, .pnm, .ppm, .tiff, .jfif, .eps*, .psd, .arw*, .tif, .dng*, .xcf*, .rw2*, .raf*, .orf*, .pef*, .mos*, .raw*, .dcr*, .crw*, .cr3*, .3fr*, .erf*, .mrw*, .mef*, .nrw*, .srw*, .sr2*, .srf*, .a*, .aai, .ai*, .art*, .avs, .b*, .bgr*, .bgra*, .bgro*, .bmp2, .bmp3, .brf*, .cal*, .cals*, .cin, .cip*, .cmyk*, .cmyka*, .dcx, .dds, .dpx, .dxt1, .dxt5, .epdf*, .epi*, .eps2*, .eps3*, .epsf*, .epsi*, .ept*, .ept2*, .ept3*, .exr, .farbfeld, .fax, .ff, .fit, .fits, .fl32, .fts, .ftxt*, .g*, .g3, .g4*, .gif87, .gray*, .graya*, .group4*, .hrz, .icb, .icon, .info*, .ipl, .isobrl*, .isobrl6*, .j2c, .j2k, .jng, .jp2, .jpc, .jpm, .jps, .map*, .miff, .mng, .mono*, .mtv, .o*, .otb, .pal*, .palm, .pam, .pcd, .pcds, .pcl*, .pct, .pcx, .pdb, .pgx, .phm, .picon, .pict, .pjpeg, .png00, .png24, .png32, .png48, .png64, .png8, .ps*, .ps1*, .ps2*, .ps3*, .psb, .ptif, .qoi, .r*, .ras, .rgb*, .rgba*, .rgbo*, .rgf, .sgi, .six, .sixel, .sparse-color*, .strimg*, .sun, .svgz*, .tga, .tiff64, .ubrl*, .ubrl6*, .uil*, .uyvy*, .vda, .vicar, .viff, .vips, .vst, .wbmp, .wpg, .xbm, .xpm, .xv, .ycbcr*, .ycbcra*, .yuv*

Audio

.mp3, .wav, .flac, .ogg, .mogg*, .oga, .opus, .aac, .alac, .m4a, .caf*, .wma, .amr, .ac3, .aiff, .aifc, .aif, .mp1*, .mp2, .mpc*, .dsd*, .dsf*, .dff*, .mqa*, .au, .m4b, .voc, .weba, .mkv*, .mp4*, .avi*, .mov*, .webm*, .ts*, .mts*, .m2ts*, .wmv*, .mpg*, .mpeg*, .flv*, .f4v*, .vob*, .m4v*, .3gp*, .3g2*, .mxf*, .ogv*, .rm*, .rmvb*, .divx*

Documents

.docx, .doc, .md, .html, .rtf, .csv, .tsv, .json, .rst, .epub, .odt, .docbook

PDF → images

.pdf*, .png*, .jpeg*, .jpg*, .webp*, .avif*, .jxl*, .gif*, .bmp*, .tiff*, .tif*, .ico*, .jp2*, .psd*, .qoi*, .tga*, .ppm*, .pgm*, .pbm*, .pnm*, .pcx*, .dds*, .exr*, .hdr*

Formats marked * support import or export only.

How to use this tool

  1. Choose files or drag them into the workspace. Matching inputs get the output format shown on this page.
  2. Check the output format and image quality for each file. Existing files in your queue keep their settings.
  3. Start the conversion, then download individual results or the completed batch. Your original files are unchanged.

Quality and format notes

Pick a lower bitrate in the conversion settings — 128 kbps or less suits speech, 192 kbps keeps music comfortable — and the workspace reports each file's new size. The audio is decoded and re-encoded, so choose the lowest bitrate that still sounds right.

Re-encoding cannot restore what the first MP3 discarded, and stacking encodings adds artifacts. For large permanent savings, re-encode from lossless originals when you have them.

Frequently asked questions

How much smaller will my MP3s get?

Going from 320 to 128 kbps cuts roughly 60% of the size; speech at 64 kbps shrinks far more. The workspace shows the exact result.

Which bitrate should I pick?

128 kbps is a solid default, 96 or 64 kbps works for voice, and 192 kbps or above keeps music comfortable.

Does compressing hurt the sound?

Lower bitrates add artifacts, and re-encoding an MP3 stacks on its existing compression. Test one file per content type before batching a library.