Terms of Use

Effective: April 21, 2026 · Last updated: April 21, 2026
These Terms govern your use of BUY or S&P?. In short: it's a free calculator, it is not financial advice, and by using it you accept these terms. If that's not acceptable, don't use the site.

Contents

  1. Acceptance
  2. The service
  3. Not financial advice
  4. Accuracy & assumptions
  5. Intellectual property
  6. Acceptable use
  7. No warranties
  8. Limitation of liability
  9. Indemnification
  10. Governing law
  11. Changes to these terms
  12. Contact

1. Acceptance

By accessing or using BUY or S&P? (the "Service"), you agree to be bound by these Terms of Use. If you don't agree, don't use the Service.

You must be at least 13 years old to use the Service. If you're under 18, use it with a parent's or guardian's supervision.

2. The service

BUY or S&P? is an opportunity-cost calculator. You enter a purchase and a price; we compute what that money would have become if invested in the S&P 500 over 1 to 30 years, using the index's long-run historical average return of 10.5% nominal annual.

The Service is provided free of charge, "as is", and we reserve the right to modify or discontinue it at any time.

3. Not financial advice

Read this carefully.

BUY or S&P? is a publication and educational tool. Nothing on this site constitutes financial, investment, tax, legal, or any other professional advice. No content should be interpreted as a recommendation to buy, sell, or hold any security, asset, or product.

Past performance of the S&P 500 — including the 10.5% annual historical average — does not guarantee future results. Indices can and do decline over any given period. Actual returns will vary.

Before making any financial decision, consult a licensed financial advisor, tax professional, or attorney as appropriate.

4. Accuracy & assumptions

The calculator uses simplified models:

  • S&P 500 growth: 10.5% nominal compound annual, applied uniformly. Real-world returns fluctuate year to year.
  • Depreciation models per category are illustrative estimates, not actuarial values. The "handbag", "watch", "car", etc. curves are designed to feel roughly realistic — they are not authoritative.
  • Inflation, taxes, fees, and dividends are not explicitly modeled. The 10.5% figure is nominal (not real) and does not account for capital-gains taxes, management fees, or transaction costs.

We make no representation that the Service is accurate or complete. Use it as a provocation — a rough sketch — not as a budgeting instrument.

5. Intellectual property

All content on BUY or S&P? — text, layout, typography, source code, and editorial voice — is the property of 1337.ai unless otherwise attributed.

You may share reckonings (screenshots, copied text, shareable URLs) freely for personal, non-commercial use. You may not copy or reproduce the site in whole or in substantial part for commercial purposes without written permission.

6. Acceptable use

You agree not to:

  • Attempt to reverse-engineer, scrape at scale, or otherwise abuse the Service
  • Interfere with or disrupt the Service or its infrastructure
  • Use the Service to harass, defame, or defraud anyone
  • Republish the Service or substantial portions of its content without permission

7. No warranties

THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE", WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED. 1337.AI DISCLAIMS ALL WARRANTIES, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. WE DO NOT WARRANT THAT THE SERVICE WILL BE UNINTERRUPTED, ERROR-FREE, OR PRODUCE ACCURATE RESULTS.

8. Limitation of liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, 1337.AI, ITS OFFICERS, EMPLOYEES, AND AFFILIATES SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES ARISING FROM YOUR USE OF (OR INABILITY TO USE) THE SERVICE — INCLUDING, WITHOUT LIMITATION, LOST PROFITS, INVESTMENT LOSSES, OR LOSS OF DATA.

You assume full responsibility for any financial decisions you make. The Service is a calculator, not an advisor.

9. Indemnification

You agree to indemnify and hold harmless 1337.ai from any claims, damages, or expenses arising out of your use of the Service or your violation of these Terms.

10. Governing law

These Terms are governed by the laws of the State of Delaware, United States, without regard to conflict-of-laws principles. Any dispute arising out of or in connection with the Service shall be resolved in the state or federal courts located in Delaware.

11. Changes to these terms

We may update these Terms from time to time. Material changes will be noted with a new "Last updated" date at the top, and continued use of the Service after such changes constitutes acceptance.

12. Contact

Questions or legal correspondence: hello@1337.ai.