For QA Engineers

Something looks different. But what, exactly?

Upload two screenshots and see every pixel that changed — layout shifts, color changes, moved elements, missing components. Set a tolerance to filter rendering noise and focus on real bugs.

Compare Files — Test Output
response-baseline.json
response-candidate.json

Diff two screenshots pixel by pixel.

Built for QA workflows.

1
Deploy sanity check

Upload a screenshot before and after your deploy. See exactly what moved, shifted, or disappeared — at pixel level.

2
Cross-browser comparison

Same page, Chrome vs Firefox. Spot layout differences that only appear in specific browsers or viewports.

3
Component regression

Before and after a UI library update. Catch subtle changes in spacing, typography, or color that slip through code review.

Compare JSON API responses.

Testing API changes? Paste two JSON payloads and see exactly what changed. Structure-aware — whitespace differences are normalized automatically. Works with YAML too.

Your files never leave your device. Ever.

Compare Files works entirely in your browser. There is no server that receives, processes, or stores your file data. Not because we promise not to look — but because we architecturally cannot. All comparison logic runs locally in JavaScript.

No AI means no hallucinations.

Compare Files uses a deterministic, logic-based engine — not a language model. It reads both files and reports every change that is actually there. It can’t summarize away a deleted line, invent a difference that isn’t in the file, or “mostly” get a number right. What you see is exactly what changed — nothing added, nothing missed. For QA, that means no AI glossing over a subtle config, copy, or rendering change.

Private

Your files never leave your device. Everything runs in your browser — no uploads, nothing stored.

Certain

No AI, so no hallucinations. A deterministic engine reports every real change and never invents one.

Fast

No upload, no server wait. Comparisons run locally and keep working offline once the page has loaded.

Common questions.

How does screenshot comparison work for visual regression testing?

Upload two screenshots and the tool highlights every pixel that differs between them — changed UI elements, layout shifts, color changes, and missing components all show up immediately. It is designed for manual spot-checks during exploratory testing, not CI pipeline integration.

What does the pixel tolerance slider do?

It controls how sensitive the pixel diff is — set it low to catch every subtle change, or raise it to filter out anti-aliasing differences and rendering artifacts that are not real regressions. This lets you focus on genuine UI bugs rather than noise from font rendering or subpixel differences.

Can I compare JSON API responses to catch breaking changes?

Yes — paste two JSON responses and Compare Files highlights every structural and value difference, including added or removed keys, changed values, and type mismatches. JSON comparison is completely free, so there is no cost for API response diffing.

Do I need to install anything or integrate it with my test suite?

No installation required — it runs entirely in your browser. It is a manual spot-check tool for moments when you need to quickly verify a screenshot or diff two API payloads during exploratory testing, without switching to a terminal or setting up tooling.

Can I also compare YAML config files to verify environment settings?

Yes — YAML and JSON config file comparison is fully supported and free. If you need to verify that a staging config matches production, or check that a deployment did not alter environment variables, paste or upload both files for an immediate structured diff.

Start catching regressions today.

No signup required for text and free features. Image comparison unlocks with Pro — €9.99/mo. Text and JSON/YAML are always free.

Compare screenshots