A static QR code encodes its destination directly into the printed pattern. There is no server involved in scanning — the decoder reads the bytes, resolves them to a URL or other payload, and that is the end of the transaction. As long as the destination is reachable, the code will keep working indefinitely. QR codes printed in 2010 still scan in 2026 because the specification has not changed.
Dynamic QR codes are a different story. They encode a short link on a provider's domain, and scanning routes through the provider's redirector before landing on the final URL. That redirector needs to stay online. With QRForge specifically, a dynamic QR works as long as your account is active; if you close the account, existing codes start returning a friendly 'this code is paused' page instead of redirecting.
Plan accordingly: if you're printing something that will live for decades — a museum placard, a tombstone, a published book — use static. If you're printing a campaign, packaging, or signage that needs to survive a redirect, go dynamic but choose a provider with a credible long-term plan, and keep a backup of your slug mappings.