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 — a 3–97 estimate

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, no sign-up — 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, no sign-up — your file is deleted as soon as the check finishes. The answer is an estimate between 3 and 97, never 0 or 100.

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 →

Deep Analysis for Every Format

Every format compares against another file. Video, images and audio are also measured on their own — no second file needed.

Video

Two files
Frame-by-frame heatmap with markers
The exact second each change appears
SSIM · PSNR similarity scores
One file
Bitrate against resolution
Focus, noise and compression over time
Padded frame rates

Image

Two files
Pixel-level difference heatmap
Structural similarity score
Flexible mode for real photos
One file
Focus and noise
JPEG blocking
Clipped highlights and shadows

Audio

Two files
MFCC spectral similarity
Per-second divergence
Waveform & spectrogram diff
One file
Loudness in LUFS
Clipping
The frequency range really present

Subtitles

Word Error Rate (WER)
Timing drift analysis
Line-by-line diff
SRT · VTT supported

Text & JSON

Semantic similarity score
Inline change highlighting
JSON structure diff
TXT · JSON · CSV · XML

Simple, Transparent Pricing

Quality checks are free on every plan. Comparisons are metered — no account needed to start, sign up for more, buy credits as you go, or go Pro for unlimited.

No Account

5 comparisons per day
Free quality checks, up to 60 a day
Video up to 3 min · audio up to 2 min
No sign-up required

Free Account

10 comparisons per day
Unlimited quality checks
Video up to 3 min · audio up to 2 min
History & API key · free sign-up

Credits

$5 one-time

50 comparisons, no subscription
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
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

Deep Analysis for Every Format

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

Deep Analysis for Every Format

Video

Image

Audio

Subtitles

Text & JSON

Simple, Transparent Pricing

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