LimitWatch: OpenAI changeshttps://ailimitwatch.com/LimitWatch: OpenAI changesOpenAI: 12-hour prompt caching option added; 12-hour cache writes cost 2.5x the input token price.https://ailimitwatch.com/entries/2026-10-20-openai-openai-api-prompt-caching/https://ailimitwatch.com/entries/2026-10-20-openai-openai-api-prompt-caching/Tue, 20 Oct 2026 00:00:00 +0000Before: No 12-hour caching option (not stated) | After: 12-hour caching available; writes at 2.5x input price | Source: https://platform.openai.com/docs/changelogOpenAI: API usage tiers simplified from five to three (Build, Launch, Grow).https://ailimitwatch.com/entries/2026-10-06-openai-openai-api-usage-tiers/https://ailimitwatch.com/entries/2026-10-06-openai-openai-api-usage-tiers/Tue, 06 Oct 2026 00:00:00 +0000Before: Five usage tiers | After: Three usage tiers: Build, Launch, Grow | Source: https://platform.openai.com/docs/changelogOpenAI: GPT-5.6 Sol price reduced to $4 input / $20 output per 1M tokens (promotional, at least through 2026-11-21).https://ailimitwatch.com/entries/2026-08-21-openai-openai-api-gpt-5-6-sol/https://ailimitwatch.com/entries/2026-08-21-openai-openai-api-gpt-5-6-sol/Fri, 21 Aug 2026 00:00:00 +0000Before: Not stated in entry (entry says new price is 20% lower input, 33% lower output) | After: $4 / 1M input, $20 / 1M output | Source: https://platform.openai.com/docs/changelogOpenAI: Fast mode replaced the Priority Processing offering; for GPT-5.6 Sol it is priced at twice standard.https://ailimitwatch.com/entries/2026-07-30-openai-openai-api-service-tiers/https://ailimitwatch.com/entries/2026-07-30-openai-openai-api-service-tiers/Thu, 30 Jul 2026 00:00:00 +0000Before: Priority Processing tier | After: Fast mode, up to 2.5x faster at twice the price (GPT-5.6 Sol); priority-tagged requests auto-use Fast mode | Source: https://platform.openai.com/docs/changelogOpenAI: GPT-5.6 Luna price cut 80% and GPT-5.6 Terra price cut 20%.https://ailimitwatch.com/entries/2026-07-30-openai-openai-api-gpt-5-6-luna-terra/https://ailimitwatch.com/entries/2026-07-30-openai-openai-api-gpt-5-6-luna-terra/Thu, 30 Jul 2026 00:00:00 +0000Before: Prior list price (not restated in the entry) | After: Luna: 80% lower; Terra: 20% lower | Source: https://platform.openai.com/docs/changelog