Every OpenAI price change CostMon tracks that actually moved a bill, cuts and increases both, with the source and what to do about it.https://costmon.comhttps://costmon.com/price-changes#gpt-5-6-luna-terra-price-cuthttps://costmon.com/price-changes#gpt-5-6-luna-terra-price-cutCiting inference-stack efficiency gains, OpenAI dropped Terra to $2/$12 per million tokens and Luna to $0.20/$1.20, while the top-tier Sol model's price stayed flat. (Luna −80%, Terra −20%) — Confirm the lower rate appears on your next invoice, then check whether tasks still pinned to Sol can safely move down to the now much cheaper Luna or Terra.Thu, 30 Jul 2026 00:00:00 GMTOpenAICuthttps://costmon.com/price-changes#gpt-5-5-price-increasehttps://costmon.com/price-changes#gpt-5-5-price-increaseGPT-5.5 launched at roughly double GPT-5.4's per-token rate. OpenAI's own announcement frames this as a deliberate increase, offset by claimed gains in token efficiency per task. ($5 / $30 per M tokens) — Run a side-by-side cost comparison on real workloads before moving production traffic. Confirm the token savings offset the higher headline price for you.Fri, 24 Apr 2026 00:00:00 GMTOpenAIIncreasehttps://costmon.com/price-changes#gpt-5-launch-pricinghttps://costmon.com/price-changes#gpt-5-launch-pricingGPT-5 launched at $1.25 per million input tokens and $10 per million output tokens, with mini and nano tiers underneath it: one family instead of separate reasoning and non-reasoning models. ($1.25 / $10 per M tokens) — Map existing GPT-4o and o3 call sites to gpt-5, gpt-5-mini, or gpt-5-nano by task difficulty, and re-benchmark spend rather than assuming a like-for-like swap.Thu, 07 Aug 2025 00:00:00 GMTOpenAIRestructurehttps://costmon.com/price-changes#gpt-4o-half-price-vs-gpt-4-turbohttps://costmon.com/price-changes#gpt-4o-half-price-vs-gpt-4-turboOpenAI's new flagship model replaced GPT-4 Turbo as the default, matching or beating its quality at half the per-token price. (−50% vs GPT-4 Turbo) — Re-point integrations at gpt-4o and re-run your eval suite before rolling it out. A cheaper model at the same price tier can still shift output style.Mon, 13 May 2024 00:00:00 GMTOpenAICut