Free no-tracking Section 16 deadline calculator for SEC Forms 3, 4, and 5 date planning, with sharper Form 4 deadline workflow copy:
- Form 3 initial beneficial ownership target from the insider status date.
- Form 4 change-in-beneficial-ownership target from a transaction or verified deemed execution date.
- Form 5 annual catch-up target from the issuer fiscal year end.
- Weekend, standard U.S. federal holiday, and optional custom closure handling.
- EDGAR 10 p.m. Eastern cutoff note, source-linked memo copy, CSV export, and ICS calendar export.
- Current foreign private issuer / HFIA Act verification reminder.
The tool runs entirely in the browser. It has no signup, cookies, analytics, beacons, external scripts, uploads, or browser storage. Calendar export creates a local .ics planning hold from the calculated target date.
Form 4 planning baseline: SEC investor materials describe the usual Form 4 deadline as two business days following the transaction date. The worksheet also keeps the Form 3 10-day and Form 5 45-day baselines visible for checklist review, without deciding reporting-person status, exemptions, or transaction treatment.
Live site: https://section-16-deadline-calculator.vercel.app/
Source: https://github.com/Turner-Levey/section-16-deadline-calculator
Tiny Tool Town listing: https://www.tinytooltown.com/tools/section-16-deadline-calculator/
Awesome SEC Filings listing: https://github.com/vibeyclaw/awesome-sec-filings#general-sec-filings
Awesome Compliance listing: https://github.com/theopenlane/awesome-compliance#open-source-platforms
Awesome OSINT listing: https://github.com/jivoi/awesome-osint#company-research
No-Login Tools listing: https://nologin.tools/tool/section-16-deadline-calculator-vercel-app/
No-Login Tools certificate: https://nologin.tools/badge/section-16-deadline-calculator-vercel-app/
Related standalone SEC tools:
- SEC Filing Fee Calculator: https://sec-filing-fee-calculator.vercel.app/
- Schedule 13D / 13G Deadline Calculator: https://sec-13d-13g-deadline-calculator.vercel.app/
- Form D Deadline Calculator: https://form-d-deadline-calculator.vercel.app/
Sources:
- Investor.gov: Insider Transactions and Forms 3, 4, and 5: https://www.investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-bulletins-69
- SEC Submit Filings / EDGAR hours: https://www.sec.gov/submit-filings
- SEC: Ownership Reports and Trading by Officers, Directors and Principal Security Holders: https://www.sec.gov/rules-regulations/2002/08/ownership-reports-trading-officers-directors-principal-security-holders
- SEC: Mandated Electronic Filing and Web Site Posting for Forms 3, 4 and 5: https://www.sec.gov/rules-regulations/2003/05/mandated-electronic-filing-web-site-posting-forms-3-4-5
- SEC: Holding Foreign Insiders Accountable Act Disclosure final amendments: https://www.sec.gov/files/rules/final/2026/34-104903.pdf
- SEC Forms Index: https://www.sec.gov/submit-filings/forms-index
This is an informational worksheet, not legal advice, securities advice, investment advice, beneficial ownership analysis, late-filing cure advice, EDGAR validation, SEC affiliation, or an EDGAR filing service.