Compare WAV vs. MP3 audio quality
Load WAV and MP3 exports of the same track and switch between them at the exact same point. You can also compare MP3 bitrates, such as 128 kbps vs. 320 kbps, or MP3 vs. lossless WAV.
Online Audio A/B Test & Comparison Tool
Compare two audio files by switching instantly at the same playback position.
Find the sections with the biggest differences, match LUFS loudness, align timing, loop sections, play the difference, and run randomized blind tests—free in your browser.
A Audio A
No file selected
WAV / MP3 / M4A / AAC / FLAC / OGG · Up to 500 MB
Your file stays on this device
B Audio B
No file selected
WAV / MP3 / M4A / AAC / FLAC / OGG · Up to 500 MB
Your file stays on this device
Listen to the anonymous A and B choices, then pick the one you prefer. The files are randomized for every trial.
A
B
Click or tap to seek. Drag to select a comparison range. The waveform shows the shared range after alignment.
Selected: A
Highlights show where the audio changes most. The size of a difference does not indicate better or worse sound.
Advanced settings
Mono files play through both left and right channels. Loudness matching accounts for this playback behavior.
A positive value skips the beginning of B; a negative value skips the beginning of A (up to ±5,000 ms).
Audio information
The original sample rate comes from file metadata; unavailable values appear as “—.” Audio is decoded at 48 kHz for comparison. Integrated LUFS and sample peak are measured from the comparison signal.
| Item | A | B |
|---|
Keyboard: Space play/pause · A / B switch · D difference · L loop · ← / → move 5 seconds (hold Shift for 1 second)
Blind test results
File mapping and response for each trial
| Trial | Preferred source file | Playback position when selected |
|---|
This is a preference test. It does not score right or wrong answers or determine which file has better audio quality.
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How to compare two audio files
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Choose audio files A and B
Add one WAV, MP3, or other supported audio file to each box.
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Play and switch between them
Once analysis is complete, start playback and switch between A and B. If one file has extra silence at the beginning, turn on Auto-align timing.
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Focus on the section that matters
Drag across a waveform to select a range, then enable Loop for repeated comparisons. Use the blind test when you want to reduce expectation bias.
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What can you compare?
A/B test a mix before and after processing
Compare a mix before and after EQ, compression, reverb, noise reduction, or other processing. LUFS loudness matching helps keep the louder version from getting an unfair advantage.
Compare masters and mastering settings
Switch between a premaster and final master, or compare two mastering versions. Both tracks stay locked to one playback position so small tonal and dynamic changes are easier to hear.
Compare MP3, AAC, FLAC, and other formats
Select WAV, MP3, M4A, AAC, FLAC, or OGG files to compare encoders, bitrates, and compression settings. Exact codec support depends on your browser.
Hear what audio processing changed
Compare audio before and after denoising, EQ, gain changes, or restoration. Difference playback isolates the part of the signal that changed.
Blind-test two mixes
Hide file names, waveforms, and analysis values while A and B are randomized for each trial. This makes it easier to choose a preferred mix or master without knowing which file is playing.
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How to run a fair audio A/B test
What is audio A/B testing?
Audio A/B testing means switching between two versions at the same playback position to hear small differences. It is useful for comparing codecs, mix or mastering revisions, and the effect of EQ, noise reduction, or other processing.
Why loudness matching matters
People often perceive a slightly louder track as sounding better. This tool measures Integrated LUFS with K-weighting and absolute and relative gating, then turns down the louder file to match the quieter one. Your original files are never modified. Loudness matching turns off when a file is nearly silent or shorter than 400 ms.
How automatic alignment works
Auto-align timing looks for a matching section within ±5 seconds to compensate for leading silence or encoder delay. It is off by default and may not work when the recordings or tempos differ. Advanced settings let you adjust timing in 1 ms steps or realign from a selected range.
Listen to the difference between two files
Difference playback subtracts B from A using the current timing alignment, without loudness matching. It can reveal changes caused by compression or audio processing, but timing and level differences are included too, so a louder difference does not mean worse sound.
This is similar to a null test, but the tool decodes both files to 48 kHz for comparison. It does not verify bit-for-bit identity between the original files.
What is the blind comparison?
The blind preference test hides file names, waveforms, and analysis results, then randomizes which source appears as A or B on every trial. Choose 5, 10, or 20 trials. At the end, the tool reveals the vote count and your choice for each trial. This is not an ABX identification test and does not produce an accuracy score.
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Frequently asked questions
Can I compare WAV and MP3 audio quality?
Yes. Export the same source as WAV and MP3, load both files, and switch between them at the same playback position. You can also enable LUFS loudness matching for a fairer comparison.
Can I compare mixes and masters?
Yes. You can A/B test two mixes, compare audio before and after mastering, or check different processing settings. Loudness matching and section looping make subtle differences easier to evaluate.
Can I compare files with different volume levels?
Yes. Automatically match loudness uses measured LUFS values to turn down the louder file to the level of the quieter one during playback. It never changes the source files. Difference playback intentionally uses the original levels.
How is this different from an ABX test?
This tool's blind mode asks which anonymous option you prefer. A traditional ABX test asks whether an unknown X matches known sample A or B and measures identification accuracy. This tool does not score correct answers.
Which audio file formats are supported?
You can select WAV, MP3, M4A, AAC, FLAC, and OGG files. Actual codec support varies by browser. If a file will not open, convert it to WAV or a standard MP3. DRM-protected and unusual formats such as HE-AAC are not guaranteed.
Are my audio files uploaded?
No. Decoding, loudness analysis, alignment, and playback all happen locally in your browser. File names and analysis results are not sent to Benri Lab's servers.
What is the maximum file size?
Each file can be up to 500 MB (500 × 1,024 × 1,024 bytes). Compressed audio becomes much larger after decoding, so long files may still exceed your device's available memory.
Can I compare files with different timing or duration?
Yes. Auto-align timing can compensate for leading silence and small timing shifts. If the shared content is too short or the tempos differ, automatic alignment may fail. When durations differ, the tool plays only the range available in both files.
Does it work on iPhone and Android?
It works in browsers that support the Web Audio API. Tap Play once to allow audio playback. Long recordings use substantial memory, so shorter files are recommended on mobile devices.