One-line summaries
- Visualping: the polished, marketing-friendly cloud monitor with great visual diffs. Built for non-technical buyers watching competitor pages.
- Distill.io: local monitoring through an extension or desktop app, plus cloud monitoring on every plan. Free includes five cloud monitors with a six-hour minimum interval.
- OnChange: the cloud-first product built for engineering and agency teams. API monitoring, WCAG scans, and a clean REST API on every plan; sub-minute checks and AI summaries on paid tiers.
Side-by-side feature matrix
| Feature | OnChange | Visualping | Distill.io |
|---|---|---|---|
| Free plan | |||
| Runs in the cloud (no browser needed) | |||
| Sub-minute check intervals | |||
| Visual (screenshot) diffs | |||
| Text and content diffs | |||
| CSS selector + XPath targeting | |||
| API / JSON endpoint monitoring | |||
| AI change summaries (plan limits apply) | |||
| Git commit attribution | |||
| WCAG accessibility scans | |||
| Slack / Discord on free plan | |||
| Custom webhooks | |||
| REST API access | |||
| Self-serve transparent pricing |
Yes, Partial, No. Based on publicly available information as of May 2026.
Where each tool wins
Visualping wins on consumer polish
Visualping has spent more than a decade refining its UX for non-technical buyers. The Chrome extension, the email digests, and the visual diff viewer feel native to a marketing workflow. If your buyer is a brand manager or PR lead, this is the lowest-friction tool to deploy. It also has the most recognizable brand in the category, which matters when you're getting purchase approval.
Distill.io wins on local-first control
Distill supports local checks while the browser or device running them remains available. Its Free plan also includes five cloud monitors, so local and cloud monitoring can be combined. Choose between them based on check frequency, device availability, and the published cloud check allowance.
OnChange wins on speed and depth
OnChange is built for teams that need detection in seconds, not minutes, and that monitor more than just pages. The four differentiators in practice:
- -Sub-minute intervals. OnChange offers 60s on Pro, 30s on Business, and 10s on Enterprise. Visualping Personal 1K allows 15-minute intervals; higher plans reach 2 minutes. Distill's local monitors can run from 5 seconds; its cloud plans range from 6 hours on Free to 2 minutes on Flexi.
- -API / JSON monitoring. Dedicated diff UI with JSONPath targeting. Visualping doesn't ship this; Distill supports it but in a more limited form.
- -Commit attribution. With an eligible connected repository, OnChange can correlate detected changes with recent commits. A correlation is a lead to investigate, not proof that a commit caused the change.
- -WCAG accessibility scans. Full axe-core scans with attested baselines. Useful for agencies and any team with compliance obligations.
Pricing snapshot
All three publish their pricing, which is a good sign. The shape of the deal is what matters.
Visualping Personal 1K is $14 billed monthly, or $120 billed annually, for 10 pages and 1,000 checks per month with intervals as short as 15 minutes. Free includes 5 pages, 150 monthly checks, and a 60-minute minimum selectable interval. The check budget limits how often all pages can be monitored throughout the month. See Visualping's pricing.
Distill.io Free includes 25 monitors, up to 5 in the cloud, with 1,000 monthly cloud checks and a 6-hour minimum cloud interval. Starter is $15 billed monthly for 50 monitors and 30,000 cloud checks with a 10-minute minimum interval. Local monitoring requires the relevant browser or desktop app to remain running. See Distill's pricing.
OnChange Free is $0 with 5 monitors at 30-min intervals, all alert channels (Slack, Discord, webhooks, email), full API access, and WCAG scans. Pro is $12/month for 50 monitors at 60s and adds visual diffs, JS rendering, and AI summaries; Business is $39/month for 300 monitors at 30s and adds multi-region monitoring.
Alert quality, in practice
One thing you can't tell from a feature matrix: what the alerts actually look like when they land in Slack. The three tools take different approaches.
Visualping sends a tidy email or Slack message with the before/after screenshots and highlighted regions. It's visually polished but text-light: you'll usually click through to understand what happened.
Distill's alerts vary by channel; the extension's in-browser badge is great for the local workflow, and the cloud tier sends compact text-first notifications.
OnChange includes an AI change summary on every alert that describes the change in plain English ("the price increased from $49 to $59 on the Pro plan; the 'Try free' CTA changed color from blue to green") alongside the diff and screenshot. For mobile triage and on-call workflows, this is the single biggest practical difference between the three.
Which one should you pick?
A decision tree, in order:
- Are you a single user with a personal watchlist? Distill.io extension is free and excellent.
- Is the primary buyer non-technical and the use case visual-only? Visualping. Polished, well-known, and the alert UX matches the workflow.
- Do you need sub-minute checks, API monitoring, or accessibility scans? OnChange. None of the other two ships all three.
- Are you an engineering team that ships code? OnChange. The commit attribution feature alone pays for itself the first time a deploy causes a regression you didn't catch.
For a deeper buying framework that's not specific to these three tools, see How to choose a change detection tool: 10 things that matter. For the full eight-tool comparison, see Best change detection software in 2026.