How do I compare two video files online?

Upload your two video files to DiffALL — it automatically calculates SSIM and PSNR frame by frame, shows a synchronized heatmap overlay highlighting every changed pixel, and identifies the exact second each difference appears. No install required, free to use.

How do I compare two images online and see the differences?

Drop two images into DiffALL. It produces a pixel-level difference heatmap alongside the original images, calculates a structural similarity (SSIM) score, and offers a flexible mode that handles rotation and lighting differences before comparing.

Can I compare SRT or VTT subtitle files online?

Yes. DiffALL supports SRT and VTT subtitle files. It calculates Word Error Rate (WER), shows a line-by-line diff with insertions and deletions highlighted, and measures timing drift — the millisecond offset between corresponding subtitle entries.

How do I compare two audio files and find differences?

Upload any two audio files (MP3, WAV, FLAC, AAC, OGG, M4A, OPUS) to DiffALL. It compares them using MFCC spectral similarity, spectral centroid, and RMS energy, and displays a spectrogram difference overlay so you can see exactly where the audio diverges.

Can I check the quality of a single video, image or audio file?

Yes, and it is free. Upload one file and DiffALL measures it against what it should be: bitrate against the published recommended rates, focus, noise, compression and exposure for images and video, and LUFS loudness, clipping and the frequency range actually present for audio — which catches a low-bitrate file re-exported at a high one. Each check gets a band from Excellent to Poor and a 0–100 score on its own scale, and the file’s overall score follows its weakest check rather than averaging them, because an average would hide the one thing that is wrong.

How do I diff two JSON files and see what changed?

DiffALL recursively flattens both JSON files into dotted key-value paths and shows a structural diff — which keys were added, removed, or changed — with inline character-level highlighting. It also handles plain text, CSV, XML, YAML, and Markdown.

How do I find visual bugs between two files?

Upload the expected and actual files to DiffALL. It highlights every visual bug with a heatmap overlay, draws bounding boxes around each changed region, and pinpoints the exact frame or area where the bug appears — so you spend zero time hunting manually.

How do I detect visual differences between two images?

DiffALL compares two images pixel by pixel and generates a colour-coded heatmap that highlights every region that differs. It also calculates an SSIM similarity score and supports a flexible mode for images that were taken from different angles or under different lighting.

How do I detect visual differences between two videos?

Upload both videos to DiffALL. It analyses every frame, overlays a heatmap on the live player to show exactly what changed and when, plots a per-second similarity graph, and flags the worst moments with timestamps — all without manual scrubbing.

DiffALL — Online Diff Tool for Video, Image & Audio Files

Two files Compare Any Two Files Voices, audio, video, images, subtitles & text One file Measure Any File’s Quality Video, images and audio — no second file needed One file Is It Made With AI? Images and video — an estimate, with its reasons

Expected

Drop file here or click to browse

Image · Video · Audio · Subtitle (SRT/VTT) · Text / JSON

Actual

Drop file here or click to browse

Image · Video · Audio · Subtitle (SRT/VTT) · Text / JSON

No files handy?

Free to use — no sign-up needed

Your file

Drop a file here or click to browse

Video, image or audio — MP4, MOV, JPG, PNG, MP3, WAV and more

No file handy? Try a sample

Free to use, no sign-up needed — each check uses one credit, like a comparison. Your any is deleted as soon as the check finishes.

Your file

Drop an image or a video here or click to browse

JPG · PNG · WebP · MP4 · MOV · WebM

No file handy? Try

Free to use, no sign-up needed — each check uses one credit, like a comparison. Your file is deleted as soon as the check finishes. The answer is an estimate, not proof — see the disclaimers below.

API Keys

One key for the whole DiffALL API — compare two files, or check the quality of one — from scripts and CI. Each call costs one credit.

No More Hunting Through Frames

Expected on the left, actual on the right, a synchronized heatmap between them — every changed region marked. You don't search for the bug. We show you where it is.

Expected

DiffALL's result: the three edited regions highlighted

Differences

Actual

Images too: three edits hidden in a busy photo — a boat removed, a boat added, a car gone from the road. Found in seconds, not by squinting.

No Reference? No Problem.

One file in, and DiffALL names each flaw in plain words, with the measurement behind it. Even the ones the file's own metadata hides.

master_final_320k.mp3 Audio quality check

34/100 Poor

Frequency range: Most of the treble is not there at all.

Bitrate 95/100 Excellent

Comfortably above transparent for this format.

3.63 bits per sample (320 kbps at 44.1 kHz, stereo)

Frequency range 35/100 Poor

Most of the treble is not there at all.

This has been through a low-quality stage somewhere, whatever the bitrate claims. Only the original recording still has the rest.

content to 10.9 kHz, of a possible 22.1 kHz at this sample rate

Clipping 100/100 Excellent

No clipped samples.

0.000% of samples at full scale, longest flat run 0 samples

A 64 kbps MP3 re-exported at 320 kbps. Every byte of metadata says 320 — the content says otherwise. Check your own file →

Supported Formats

Compare any two. Video, images and audio can also be checked on their own.

Video

MP4MOVMKVAVIWebM

Two files
Change heatmap
Exact timestamps
SSIM & PSNR
One file
Bitrate
Focus & noise
Frame rate & shake

Image

JPGPNGWebPGIF

Two files
Difference heatmap
Similarity score
Works on real photos
One file
Focus & noise
JPEG blocking
Clipped highlights

Audio

MP3WAVFLACAAC

Two files
Spectral similarity
Per-second diff
Spectrogram view
One file
Loudness (LUFS)
Clipping
Real frequency range

Subtitles

SRTVTT

Two files
Word error rate
Timing drift
Line-by-line diff

Text & JSON

TXTJSONCSVXML

Two files
Similarity score
Highlighted changes
JSON structure diff

Simple, Transparent Pricing

Every comparison and every check uses one credit — no account needed to start, sign up for more, buy credits as you go, or go Pro for unlimited.

No Account

5 comparisons or checks per day
Quality checks and AI check included
Video up to 3 min · audio up to 2 min
No sign-up required

Free Account

10 comparisons or checks per day
Quality checks and AI check included
Video up to 3 min · audio up to 2 min
History & API key · free sign-up

Credits

$5 one-time

50 credits — one per comparison or check
Quality checks read up to 3 min of a clip
Whole videos compared end to end · bigger files
Buy again anytime you run out

Best Value

Pro

$9 / month

Unlimited web comparisons and checks
Quality checks read up to 3 min of a clip
Whole videos compared end to end · bigger files
500 API calls / month — compare or check

Volume

Enterprise

Custom tailored to your volume

Everything in Pro
More API calls than Pro's 500 a month
A monthly allowance sized to your volume
Direct email support

Compare Any Two Files.
Or Measure the Quality of One.

API Keys

No More Hunting Through Frames

No Reference? No Problem.

Built for Testers Who Need Answers, Not Just a Player

Supported Formats

Video

Image

Audio

Subtitles

Text & JSON

Simple, Transparent Pricing

Compare Any Two Files.Or Measure the Quality of One.

Choose a tool

API Keys

No More Hunting Through Frames

No Reference? No Problem.

Built for Testers Who Need Answers, Not Just a Player

Supported Formats

Video

Image

Audio

Subtitles

Text & JSON

Simple, Transparent Pricing

Compare Any Two Files.
Or Measure the Quality of One.