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Bot403

Blocks spam form submissions by having the browser solve a proof-of-work challenge that the server verifies in one call.

Free plan · From ≈ $2.24/moActively maintained

ProductivitySecurityFree tier
bot403.com ↗
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Bot403: data, price, alternatives
At a glancechecked Oct 23, 2026

not read yet

Use

For
site owners and developers whose HTML forms get spam and who want no captcha
Price
Free plan · From ≈ $2.24/mo€2 · pricing page, read Oct 29, 2026
Activity
Actively maintainedrelease 11 days ago · site updated 11 days ago
Company
Domain since 2026 (registered this year) · ~1 peopledomain registered · per their About page
How it runs
API
Used for
  • add invisible bot checks to contact forms
  • verify form submissions on the server before processing
  • let an AI assistant install protection into a project
read off bot403.com on Oct 29, 2026
Worth knowingcomputed from what we read · each with its source
Pricingpricing page, read Oct 29, 2026

Free plan · From ≈ $2.24/mo

€2

pricing page

Price Watch: every price change in the Atlas, weekly

The companyeach fact with its source · read Oct 29, 2026
Your datawhat they publish, each line with its page · read Oct 29, 2026

These are Bot403's own statements, read from its pages. We did not audit them. A line that is missing was not found on the pages we read; it does not mean the practice is absent.

How a program reaches itfound, not claimed · read Oct 29, 2026
  • MCP servercom.bot403/bot403verified in the MCP registry
  • Stateanswers, requires sign-inchecked 2026-10-29
  • Address to connectbot403.com/mcp
  • OpenAPI spec18 pathsthe spec ↗
  • MCP docsbot403.com/docs/mcpthe vendor's page ↗
  • Status pagelinked from the homepagebot403.com/status ↗

MCP server details →

This card as JSON, for your agent →

Each line is something a program found when it went looking: the registry entry, the server's own answer, a spec that parses. A missing line means we did not find it, not that it does not exist.

Alternatives in Productivityby use, among tools still maintained

Figure and bar: visits/mo, estimate · year: online since

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Questions this page answers
  • What is Bot403?

    Blocks spam form submissions by having the browser solve a proof-of-work challenge that the server verifies in one call. It is listed in the Atlas under Productivity.

  • Who is Bot403 for?

    site owners and developers whose HTML forms get spam and who want no captcha

  • How much does Bot403 cost?

    Bot403 has a free plan; paid plans start at ≈ $2.24/mo (€2/mo), per its pricing page on 2026-10-29.

  • Is Bot403 free?

    Yes, Bot403 has a free plan, per its pricing page on 2026-10-29.

  • Is Bot403 still maintained?

    Actively maintained: release 11 days ago · site updated 11 days ago.

  • Is Bot403 safe?

    We do not audit vendors. What Bot403 publishes, read 2026-10-29: GDPR stated on its privacy policy.

  • How do I cancel Bot403?

    In its own words (terms of service, 2026-10-29): “You can cancel at any time in Settings or through Link.”

  • Does Bot403 give refunds?

    In its own words (terms of service, 2026-10-29): “You can get a full refund of your first payment: email me within 14 days.”

  • What are alternatives to Bot403?

    In Productivity, by use: ScreenshotInk, Kanshi, splitforms, formpaste, ShipMyForm.

How we read a tool

No votes, no reviews, no vendor claims. Every week a crawler reads each tool's own site and a few public registries, and the words on the card are bands over what it read.

  • Use: visits to the site (estimated), installs from npm and PyPI, presence in Chrome's usage report.
  • Activity: the newest release on GitHub, npm or PyPI; the newest dated page on the site; open roles on a public jobs board.
  • Price: the vendor's own pricing page, read with the date. A figure is printed only when it is on that page.
  • The line and the use cases are written by us from the homepage, one tool at a time, and refused when they repeat the vendor's marketing.

How AI assistants read each site — the reading vendors ask us about — is on each tool's own visibility page.

How we read every tool → · By INITE Atlas Desk