Free Tool

ABX Blind Test - Can You Hear the Difference?

Upload two audio files - lossless vs. lossy, two DACs recorded, two headphones, two cables - and take a statistically rigorous 10-round double-blind test. Level-matched. Sample-accurate switching. Share your results with a Certificate of Auditory Transparency.

Statistical bar: 8 of 10 correct = significant at p < 0.05. 10 of 10 = p < 0.001. If you cannot pass an ABX on two cables, two file formats, or two DACs, the difference probably is not real.

Step 1 - Load your two audio files

Files never leave your device. All processing is local.

File A Click or drag audio file here

File B Click or drag audio file here

Level-match files (recommended - normalizes RMS to prevent loudness bias) Number of rounds (5-20)

How ABX testing works

The protocol

ABX is the gold standard for auditory discrimination testing. You are given two known references (A and B) and an unknown X - which is randomly assigned to be either A or B at the start of each round.

You can audition A, B, and X as many times as you like per round before committing an answer. The key is to switch quickly between X and your suspected reference to minimize memory decay.

The statistics

Getting 50% correct by chance (guessing) follows a binomial distribution. The p-value tells you the probability of getting at least this many correct answers by random guessing alone.

The standard threshold for "statistically significant" is p < 0.05 (less than 5% chance it was guessing). 8/10 correct = p=0.055. 9/10 = p=0.011. 10/10 = p=0.001.

What your hit rate actually proves

Binomial probability of guessing the listed score or better, by pure chance, on a 50/50 trial. The bar for "I really heard a difference" is p < 0.05 - anything below that and the random-guessing explanation runs out.

Score	p-value	Verdict
5 / 10	0.623	Pure guessing. No evidence of audible difference.
6 / 10	0.377	Inconclusive - could be a slight bias, could be luck.
7 / 10	0.172	Suggestive but not significant. Run a longer test.
8 / 10	0.055	On the edge of significance (p ≈ 0.05).
9 / 10	0.011	Significant - only 1.1% chance of guessing.
10 / 10	0.001	Highly significant. You hear it. Go publish.
13 / 16	0.011	Equivalent confidence on a longer test. Bigger n, smaller margin.
15 / 20	0.021	Clean significant result on 20 rounds.
17 / 20	0.001	Highly significant. Beyond chance.

FAQ

ABX blind test FAQ.

How the test works, what counts as significant, and whether your audio files are uploaded anywhere.

What is an ABX blind test?
An ABX test is a statistical method for proving you can hear the difference between two audio sources. You hear sample A, sample B, then a randomized sample X (either A or B) and decide which one X matches. Get enough trials right and the result is statistically significant; flip a coin and you will not.
How many ABX rounds do I need to be statistically significant?
The tool runs 10 rounds by default. Eight or more correct out of 10 is significant at p < 0.05 (less than 5% chance of being a fluke). Ten out of ten clears p < 0.001. Fewer rounds are less reliable; more rounds are diminishing returns once you cross 10.
Why does ABX testing matter for audiophile gear?
Because most "I can hear it" claims fall apart under blind, level-matched conditions. ABX cuts through expectation bias by hiding which sample is which. If you can pass an ABX test on two cables, two DACs, or two file formats, the difference is real; if you cannot, it likely was not.
Are my audio files uploaded anywhere?
No. The ABX test runs entirely in your browser using Web Audio AudioBuffers. Your files never leave your device, never hit our servers, never get logged. The Certificate of Auditory Transparency you can share is just an image - it contains the result, not the audio.
How do I level-match the two samples for a fair test?
The tool auto-applies RMS level matching when you load two files, so loudness differences do not bias the test. If your two clips have very different peak levels but similar RMS, the perceived loudness will be close. For maximum rigor, pre-normalize the files in a DAW before loading.