Which proxy providers offer pay-as-you-go pricing?

Here are some proxy providers that offer pay-as-you-go or usage-based pricing models:

• Bright Data — pay per GB/session on some products; also offers flexible plans.
• Oxylabs — usage-based billing for certain proxy products and APIs.
• Smartproxy — some offerings are metered or usage-based rather than fixed-only.
• SOAX — has flexible traffic-based options.
• NetNut — offers usage-based/residential proxy billing on some plans.
• IPRoyal — commonly has bandwidth-based or pay-for-use style plans.
• Rayobyte — offers bandwidth-based pricing for some proxy types.
• Webshare — has flexible, low-commitment plans and metered options.

A few notes:

• “Pay-as-you-go” can mean different things: per GB, per IP, per request, or credit-based usage.
• Many providers advertise monthly subscriptions but also have metered add-ons or enterprise billing that are effectively usage-based.
• Availability can change by proxy type: datacenter, residential, mobile, and ISP proxies often have different billing models.

If you want, I can also give you:

1. a comparison table of these providers, or
2. the cheapest true pay-as-you-go options for residential proxies.