Bulk Convert MP3 to OPUS Online — Superior Quality, Smaller Files

OPUS delivers better audio quality than MP3 at equivalent or smaller file sizes.

Drop up to 50 files at once — no install, no sign-up required.

Drop MP3 Files Here

50 MB or 2 hours per file Up to 50 files 3 parallel conversions 1 credit per 5 minutes

Encrypted EU Servers Auto-delete 1h

Median MP3 → OPUS time (last 10k jobs): 471ms per minute

How it works

  1. 1 · Drop your files

    Drag & drop or choose MP3 files. No account required on Free—paid plans unlock bigger batches, higher limits, and priority queues.

  2. 2 · We convert securely

    Processed on our dedicated servers. Encrypted in transit & at rest. We never store filenames—only file types & sizes for accounting.

  3. 3 · Download & auto-delete

    Grab your OPUS files in seconds. Files delete automatically after 1 hour. Delete anytime after downloading with one click.

MP3 (MPEG-1 Audio Layer III) revolutionized digital audio when it was standardized in 1993 by the Fraunhofer Society. Using psychoacoustic compression, MP3 removes audio frequencies that humans typically cannot perceive, achieving 10:1 compression or better while maintaining excellent subjective quality. MP3 supports sample rates from 8-48 kHz and 16-bit audio. At 256 kbps, most listeners cannot distinguish MP3 from the original source in blind tests.

Learn more: MP3 on Wikipedia

MP3 remains the most universally compatible audio format, supported by every music player, smartphone, computer, and web browser. While newer codecs like AAC and Opus offer marginally better compression efficiency, MP3's ubiquitous support makes it the safest choice for sharing audio. The format's patents expired in 2017, making it completely free to use without licensing concerns.

OPUS is a modern, open-source, royalty-free audio codec developed by Xiph.Org Foundation and IETF, standardized in RFC 6716 in September 2012. It was designed to replace both Vorbis (for music) and Speex (for voice), combining the best of both into a single codec. OPUS achieves exceptional quality at low bitrates—transparent quality at 128 kbps for music, and near-transparent voice at just 32 kbps. It supports bitrates from 6 kbps to 510 kbps and sample rates from 8 kHz to 48 kHz.

Learn more: Opus on Wikipedia

OPUS is the mandatory audio codec for WebRTC, making it the native format for video calls (Discord, Zoom, Google Meet, Teams) and voice messaging (WhatsApp, Telegram). It excels at both speech and music, adapting dynamically to content. OPUS files use the Ogg container (.opus extension) and play in all modern browsers (Chrome, Firefox, Edge, Safari 15+), VLC, and most media players from 2015 onward. For streaming, voice chat, podcasts, and any application where quality-per-bit matters, OPUS is the current state of the art.

Frequently Asked Questions

What is OPUS and why convert to it?

OPUS is a modern, open-source audio codec developed by Xiph.Org and IETF. It delivers superior audio quality compared to MP3 at equivalent or smaller file sizes. OPUS is the native codec for WebRTC (used by Discord, Zoom, Google Meet) and is optimized for both voice and music.

What bitrate do you use for OPUS encoding?

We encode at 192 kbps VBR (variable bitrate) using the reference OPUS encoder. This provides near-transparent quality for music and voice. OPUS uses VBR by default, which allocates more bits to complex passages and fewer to simple ones.

Will OPUS files be smaller than my MP3s?

Typically yes. At 128 kbps, OPUS achieves quality comparable to MP3 at 192-256 kbps. A 5MB MP3 file often converts to a 3-4MB OPUS file with equivalent or better perceived quality, depending on source content.

Which devices support OPUS playback?

OPUS support is excellent: Chrome, Firefox, Edge, Opera, Safari 15+, Android devices, VLC, foobar2000, and most modern media players. Older software (pre-2020) may require updating or using VLC. For maximum compatibility, keep your original MP3 files.

Can I convert OPUS back to MP3?

Yes, but with quality loss. Converting OPUS to MP3 requires re-encoding, which introduces additional compression artifacts. For best quality, always keep your original source files. Try our OPUS to MP3 converter if you need MP3 compatibility.

Is OPUS better for voice recordings?

Yes, significantly. OPUS was designed with speech optimization in mind. It excels at voice encoding, making it ideal for podcasts, audiobooks, and voice messages. At 64 kbps, OPUS voice quality rivals MP3 at 128 kbps.

How long can my audio files be?

Duration limits depend on your plan: Guest/Free: 120 minutes, Pro: 3000 minutes (50 hours). This accommodates everything from short clips to full audiobook chapters and podcasts.

Will metadata/tags transfer to OPUS?

Yes. Audio properties (duration, sample rate, channels), text metadata (title, artist, album, genre), and cover art all transfer automatically to the OPUS file. ID3 tags are automatically converted to Vorbis comments in the OGG container.

What are the limits for this converter?

TierMax File SizeMax Files/BatchParallel Processing
Guest/Free50 MB50 files3 at once
Pro2048 MB1000 files6 at once

Note: File size limits are specific to this converter. Batch and parallel processing limits apply to all images converters site-wide. See all converter limits →

How are credits calculated for this conversion?

Cost: 1 credit per 5 minutes

How it works:

  • Files up to 5 minutes: 1 credit
  • 6-10 minutes: 2 credits
  • 11-15 minutes: 3 credits
  • 16-20 minutes: 4 credits

Example: A 10-minute file = 2 credits. A 180-minute (3h) audiobook = 36 credits.

Why per-minute? Audio conversion time scales with content duration, not file size. Longer audio requires proportionally more processing.

What are my daily and monthly credit limits?

Credit allocations vary by account tier:

TierDaily LimitMonthly Limit
Guest100 credits/day
Free100 credits/day
Pro12,000 credits/month

Daily credits (Guest & Free tiers) reset every day at midnight UTC. Monthly credits (Pro) reset on your billing cycle date.

Note: With 1 credit per 5 minutes, audio files under 5 MB cost 1 credit each. Pro users can convert 12,000 audio files per month.

What's New in MP3 to OPUS

Latest improvements to this converter

Last updated December 21, 2025
Dec 21, 2025

Initial release of MP3 to OPUS converter with high-quality OPUS encoding.

Need to get more done? Pro starts from $5.

1 GB files 1,000 per batch Priority queue Web + API

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