Convert files in your browser -
nothing is uploaded, ever.

Every tool runs entirely in-browser. No server. No account. Fully private and works offline once loaded.

No Upload 100% Private Works Offline Free
Browse All Tools How it works ↓

Tools by category

Image Tools

See all →
HEIC to JPG
Convert iPhone photos to JPG
→
Image Resizer
Resize images to any dimension
→
Image Cropper
Crop images with visual tool
→
Image Compressor
Shrink any image without quality loss
→
TIFF to JPG
Convert TIFF photos and scans to JPG
→
WebP to JPG
Convert WebP for wider compatibility
→

PDF Tools

See all →
PDF to JPG
Convert PDF pages to images
→
PDF Compressor
Reduce PDF size without uploading
→
Merge PDF
Combine multiple PDFs into one
→
JPG to PDF
Turn JPG images into a PDF
→

Video Tools

See all →
MKV to MP4
Convert downloaded videos to MP4
→
GIF to MP4
Convert GIF animations to video
→
Video Trimmer
Cut and trim video clips
→
MP4 to MP3
Extract audio from video files
→

Audio Tools

See all →
MP3 Cutter
Cut and trim any audio file
→
WAV to MP3
Convert WAV to compressed MP3
→
MP3 to WAV
Convert MP3 to uncompressed WAV
→
FLAC to MP3
Convert lossless FLAC to MP3
→

AI Tools

See all →
Background Remover
Remove image backgrounds with AI
→
Image to Text (OCR)
Extract text from any image
→
AI Image Upscaler
Upscale images 2x or 4x with AI
→
Speech to Text
Transcribe audio and video files
→
Image Captioning
Auto-generate image descriptions
→
Smart Compressor
Compress to exact target file size
→
Face Blur
Anonymize faces in photos
→
Noise Reduction
Remove grain from photos
→

Dev Tools

See all →
JSON Formatter
Beautify and validate JSON
→
JS Minifier
Minify or beautify JavaScript
→
CSS Minifier
Minify or format CSS code
→
SQL Formatter
Format SQL queries instantly
→
HTML Formatter
Format or minify HTML code
→
Gradient Generator
Create CSS gradients visually
→

Utility Tools

See all →
BMI Calculator
Calculate Body Mass Index instantly
→
Age Calculator
Calculate exact age from birthdate
→
Color Picker
Pick colors from image or screen
→
Unit Converter
Convert between any units
→

Why OfflineConverter?

Your files never leave your device.

Every tool on this site runs using browser APIs - WebAssembly, Canvas, FileReader. When you select a file, it is read into memory in your tab and processed locally. The result is streamed back to you as a download. No byte of your data is ever sent to our servers or any third party.

  • No cloud storage - files are never stored anywhere
  • No account required - open a tool and go
  • No file size limits imposed by upload quotas
  • GDPR compliant - no data processing on our end

How it works

1

Select a file

Pick any file from your device. Nothing leaves your computer.

2

Browser processes it

The tool runs locally in your browser using JavaScript - no server involved.

3

Download the result

Your converted file downloads instantly. Nothing is sent to any server.

Browse by category

Offline Image Converter
HEIC, AVIF, WebP, PNG, JPG and more
Secure PDF Converter
Merge, split, rotate, compress - all offline
Offline Video Converter
Compress, convert, extract audio locally
Browser Dev Tools
JSON, CSV, Base64, UUID and more

Frequently asked questions

Does anything actually get uploaded?

No. Every tool processes files entirely in your browser. No data is ever transmitted to any server.

Can I use these tools without an internet connection?

Yes - once the page has loaded, most tools work fully offline using JavaScript in your browser tab.

Is there a file size limit?

There is no server-imposed limit. The practical limit is your device's available RAM. Files up to a few hundred MB work well in most modern browsers.

Which file formats are supported?

We support JPG, PNG, WebP, AVIF, HEIC, SVG, BMP, GIF, PDF, MP4, MOV, MKV, AVI, MP3, JSON, CSV, YAML, Base64, and more - 81 tools in total.

Guides & Articles

View all articles →
How-To
How to Merge PDF Files for Free (No Upload Required)
Step-by-step guide to merging PDF files in your browser for free. No software or uploads needed.
Read →
 Mobile Photos
Convert iPhone Photos to JPG Offline: Ultimate HEIC Guide
Convert HEIC photos to JPG for universal compatibility. Share iPhone photos on any device.
Read →
 How-To
How to Format JSON Online for Free (Offline & Private)
Format and beautify JSON in your browser for free. No data sent to servers — works completely offline.
Read →
 Image Optimization
Compress Images Offline: Reduce File Size Without Quality Loss
Optimize image file sizes offline while maintaining quality. Perfect for web, email, and storage.
Read →
 Privacy
Why You Should Never Upload Files to Convert Them
Uploading files to online converters exposes your data. Learn why offline conversion is always safer.
Read →
 Audio Conversion
Extract Audio from Videos Offline: MP4 to MP3 Guide
Convert MP4 videos to MP3 audio files offline. Extract music, podcasts, and audio with complete privacy.
Read →