Best File Size Converter Apps

249+ iOS apps curated and reviewed

4.7 avg rating
20 free apps
Updated October 2026

Every iPhone needs a few good file size converter apps. We benchmark 249+ of them on App Store rating, freshness, and pricing, then surface the standouts so you don't have to scroll the App Store yourself.

Compare top File Size Converter Apps (October 2026)

#AppPriceRatingAdsIn-App PurchasesUpdated
1File Size ConverterFile Size ConverterFree—NoYesSep 2026
2Compress Photos & PicturesCompress Photos & PicturesFree4.7★ (23K)YesYesNov 2026
3SlimSpace - CompressorSlimSpace - CompressorFree4.6★ (1K)YesYesNov 2026
4Audio Converter - MP3 & MoreAudio Converter - MP3 & MoreFree4.5★ (2)NoNoOct 2026
5Convertelier: File ConverterConvertelier: File ConverterFree—NoYesOct 2026
6Convertly: File ConverterConvertly: File ConverterFree5.0★ (2)NoNoOct 2026
7Verto — File ConverterVerto — File ConverterFree—NoNoAug 2026
8Pixzool: Photo ConverterPixzool: Photo ConverterFree—NoYesJul 2026

Top Picks for File Size Converter

Compress Photos & Pictures#2

Compress Photos & Pictures by New Marketing Lab, Inc

Reduce image size, free space
Strong Contender
📷 Photo & Video
4.7😐(23K ratings)
FreeAdsIn-App Purchases
Compress Photos & Pictures screenshot 1
Compress Photos & Pictures screenshot 2
Compress Photos & Pictures screenshot 3
Compress Photos & Pictures screenshot 4
Compress Photos & Pictures screenshot 5

Reduce the file size of your photos and reclaim storage space on your device. This app offers intelligent compression to maintain image quality while significantly shrinking files for faster sharing and easier storage. It supports various file types and offers advanced tools for privacy and export.

What We Love

  • 👍 Easy to use
  • 🚀 Effective compression
  • 💡 Useful for reducing photo file size
  • 🚀 Fast processing
  • 🚀 Saves a lot of storage space

Room to Improve

  • 🐛 Compression issues (photos look distorted or washed out)
  • 🐛 Crashes or freezes during batch processing
  • 🔍 Difficult to find compressed photos in library
  • 💰 Aggressive ads in free version
  • 💰 Paid version still has ads
SlimSpace - Compressor#3

SlimSpace - Compressor by HappyTimes Tech Co., Ltd.

Compress photo & video offline
Worth Considering
📊 Productivity
4.6😐(1K ratings)
FreeAdsIn-App Purchases
SlimSpace - Compressor screenshot 1
SlimSpace - Compressor screenshot 2
SlimSpace - Compressor screenshot 3
SlimSpace - Compressor screenshot 4

Free up device storage by reducing the size of photos and videos. This app offers offline compression with advanced algorithms to maintain quality. It supports various file formats and includes tools for cleaning up your photo library.

What We Love

  • 👍 Easy to use
  • 🚀 Fast compression
  • 💡 Useful compression options
  • ✨ Good quality compression
  • 💾 Saves storage space

Room to Improve

  • 🐛 Crashes and freezes
  • 💸 Aggressive upselling and ads
  • 🔍 Confusing interface
  • 🤔 Inconsistent performance
  • 🔒 Unreliable paid features

More File Size Converter apps to explore

FAQ about File Size Converter

Are there free file size converter apps for iPhone?
Yes — 20 of the top file size converter apps we rank are free to download, including File Size Converter and Compress Photos & Pictures.
File Size Converter has no ads and offers in-app purchases, according to its App Store listing as of October 2026.
We track 249+ file size converter apps on the iOS App Store as of October 2026, ranked by rating, recency, and analysis of real user reviews.