Posts in the AI Pricing Watch series
DeepSeek V4-Pro peak Output jumped from $0.87 to $3.96/1M tokens (↑355%), V4-Flash from $0.28 to $1.32 (↑371%), effective 2026-08-16 16:00 UTC. Off-peak rates are half of peak (peak hours: 01:00-04:00 and 06:00-10:00 UTC). Post-hike prices still undercut GPT-5.6 and Claude, but the low-cost moat has narrowed significantly.
Claude Sonnet 5 was set to jump from its promo price of $2/$10 to $3/$15 on 9/1. On 8/10 Anthropic updated its pricing page to confirm the increase 'will not happen' — $2/$10 is now the permanent price. For a workload of 300K customer-service conversations per month, that avoids a $1,200/month cost increase (↓33%), and means Sonnet 5 is now permanently cheaper than its predecessor Sonnet 4.6 ($3/$15).
GPT-5.6 Sol standard rates through OpenRouter and Cloudflare AI Gateway drop from $5.00/$30.00 to $2.50/$15.00 per million tokens (input/output, -50%); Flex goes as low as $1.25/$7.50. Promo runs through 2026-09-18. Discount applies only to platform-managed billing (Unified Billing / non-BYOK) traffic — OpenAI's own API pricing is unchanged.
OpenAI officially lowered GPT-5.6 Sol standard rates from $5.00/$30.00 to $4.00/$20.00 per million tokens (input/output; input ↓20%, output ↓33%), effective 2026-08-21, promotional period at least through 11/21. This is OpenAI's own price cut — not an OpenRouter/Cloudflare-style platform promo (see previous post). The two now stack: OpenRouter's 50% discount applies on top of the new $4/$20 base, yielding $2.00/$10.00.
Google Cloud added Flexible Savings Plans for Gemini Enterprise (spend-based monthly commitment, 10% off for 1-year, 20% off for 3-year, no minimum or maximum), a new pay-as-you-go consumption edition, and an upcoming off-peak batch processing option (up to 50% off inference cost), effective 2026-08-26. Unlike OpenAI's GPT-5.6 Sol sticker-price cut, this doesn't touch list prices at all — it's a whole new billing toolkit. Where OpenAI is fighting a price war, Google is fighting a FinOps-governance war.
Effective 2026-08-23 00:00 Beijing time, DeepSeek no longer distinguishes peak from off-peak hours on Saturdays and Sundays — the entire weekend now bills at the off-peak rate. Previously, weekends followed the same schedule as weekdays, with V4-Pro output costing $3.96/1M tokens during peak windows; now weekends are $1.98/1M all day. Weekday billing is unchanged. This lands just one week after the 8/16 peak-hour price hike (output up 355%-371%).
OpenAI's Assistants API (/v1/assistants, /v1/threads, /v1/threads/runs) officially sunset on 2026-08-26 — announced a year in advance, zero grace period, no automated migration tool. This isn't a pricing change on its own, but the forced migration also forces a model choice: workloads that ran on o3 ($2.00/$8.00 per million input/output tokens) via Assistants have no direct successor. OpenAI's official recommendation is GPT-5.6 Sol ($4.00/$20.00, cost ↑129%), but Terra ($2.00/$12.00, ↑29%) is often good enough in practice — a 44% gap between the two paths.
Anthropic released Claude Fable 5.1 on 9/1: base input/output pricing is unchanged at $10/$50 per million tokens, but cache reads dropped from $1.00 to $0.25 (↓75%), saving up to 45% on cache-heavy agentic workloads. Google released Gemini 3.8 Flash on 9/2 at an introductory $0.75/$3.75, good only through 2026-12-31 — standard pricing doubles to $1.50/$7.50 starting 2027-01-01.
OpenAI announced on 2026-09-14 that GPT-5.5 will retire from ChatGPT, ChatGPT Work, and Codex on 2026-10-14 — but calling `gpt-5.5` directly through the OpenAI API is unaffected. This is a product-surface retirement, not an API sunset. On the official pricing page, gpt-5.5's short-context input/output is $5.00/$30.00 per million tokens; the officially recommended Codex replacement, GPT-5.6 Sol, is $4.00/$20.00 — cheaper on both input (↓20%) and output (↓33%). The gap between announcement and shutdown is one month, far shorter than OpenAI's own documented minimum of six months' notice for GA models.
xAI's official pricing docs announced that starting 2026-09-21 12:00 PT, the Grok API's `x_search` tool switches from a flat $5 per 1,000 tool calls to $5 per 1,000 posts fetched plus $10 per 1,000 user profiles fetched — and parent/quoted posts returned inside a thread count toward that total. Other tools like `web_search` and `code_execution` stay at a flat $5 per 1,000 calls. Light queries that return only a handful of results are barely affected, but social-monitoring agents that pull full threads and average dozens of posts per query could see their bill go up, not down.
Perplexity's pricing docs and migration guide confirm that Sonar Chat Completions (sonar, sonar-pro, sonar-reasoning-pro, sonar-deep-research) stops being supported on 2026-09-27, fully replaced by the Agent API. The old model billed model token price plus a flat request fee tiered by search depth ($5-$12 per 1,000 requests); the new model bills whatever third-party model token price you pick (e.g. gpt-5.6-luna at $0.20/1M input) plus per-tool-call fees (web_search at $0.0025, fetch_url at $0.0005). Using Perplexity's own representative usage figures, Sonar-to-fast comes out about 49% cheaper, Sonar Pro-to-low about 84% cheaper, and Sonar Reasoning Pro-to-medium about 71% cheaper. But sonar-pro and sonar-reasoning-pro stop being routable outright on most third-party gateways — only the base sonar model gets auto-migrated to the Agent API, and every other tier requires a manual switch to the new preset system.
OpenAI's launch post and pricing page confirm GPT-6 Sol input dropped from $4.00 to $2.00/1M tokens (-50%), output from $20.00 to $10.00 (-50%); GPT-6 Luna input dropped from $0.20 to $0.10 (-50%), output from $1.20 to $0.50 (-58%), effective 2026-09-22. The baseline for the cut is GPT-5.6's promotional pricing, not its list price — and OpenAI's own pricing page notes that GPT-5.6 Sol's promo rate is only guaranteed through 2026-11-21. That means GPT-6 Sol's new $2/$10 is the real long-term number to compare against, not the promo it's being measured against.
Claude Sonnet 5.5 launched on 2026-09-29 at the exact same API rate as Sonnet 5: $2.00 input, $10.00 output, $0.20 cache read (all USD/1M tokens) — a 0% price change. Anthropic's headline claim of 'up to 30% less' comes from needing fewer tokens and fewer tool calls per task, not a lower per-token rate, so the actual savings you see depend entirely on whether your workload benefits from that efficiency gain — it's not a guaranteed number.
On 2026-09-29, OpenAI's DevDay added an Ultrafast speed tier to the GPT-6 Astra API: input/output priced at 6x Standard (short context: $60/$300 per 1M tokens) in exchange for up to 6x faster generation via the API and 8x in Codex. In the same announcement, ChatGPT Pro 200's Codex/Work usage allowance dropped from 20x Plus to 10x Plus — existing subscribers keep their old allowance until 2026-10-29, then receive a one-time $2,500 usage credit that expires 2026-12-31. The new Pro 500 plan ($500/month, 25x Plus usage) is now the only subscription tier that includes Ultrafast.
xAI's grok-imagine-image-quality retires on 2026-11-02 (60-day notice given 9/2). After that date, every request is silently redirected to grok-imagine-image-2.0 with quality forced to low, dropping the price from $0.05 to $0.04 per image (↓20%). The catch: grok-imagine-image-2.0 itself doesn't price by quality tier — anyone who migrates proactively and explicitly sets quality: medium gets better output at the exact same price, while anyone who just waits for the redirect gets stuck on the lowest tier.
Google announced Gemini 4 Argon on 2026-09-30 with an introductory API price of $2.00 input / $10.00 output per 1M tokens (cached input $0.10). Once the introductory period ends, the standard price doubles to $4.00/$20.00 (cached $0.20) — a 100% jump. The announcement only says the increase kicks in 'after the introductory period expires,' with no actual date, and Argon is currently limited to trusted cybersecurity partners with no timeline for general API access.
Starting 2026-10-09, Google cuts the free Gemini App's model lineup (personal accounts) from Flash-Lite/Flash/limited Pro down to Flash-Lite only. AI Plus ($7.99/month) loses Pro access but keeps Flash. AI Pro ($19.99/month) and AI Ultra are unaffected, and AI Pro now also gets Deep Think, a feature previously exclusive to Ultra. This isn't a Gemini API or AI Studio pricing change — it's purely a usage-policy tightening on the consumer app.
On 10/6, Anthropic expanded Claude for Startups from a vague "we provide credits" offer into three concrete, dollar-denominated benefits: 5 free Claude Team Premium seats for a year (worth $7,500 at the official $125/seat/month rate), a one-time $1,000 API credit (expires in 6 months), and up to $45,000 in partner tool discounts. Eligibility is unchanged: founded within 5 years, or funded within the last 2.
On 2026-10-07, Anthropic cut Claude Sonnet 5.5's cache-read (cache-hit) price from $0.20 to $0.10 per 1M tokens — down from 10% of the input price to 5% — effective the same day. Input ($2), output ($10), and cache writes (5-minute $2.50, 1-hour $4) are unchanged. This is the first real price change for Sonnet 5.5 since its 9/29 launch: at launch Anthropic insisted the headline rates hadn't moved and the savings came entirely from using fewer tokens per task.
Starting 2026-10-07, Anthropic is rolling out free monthly Claude API credits for subscribers: $100/month on Max 5x, $200/month on Max 20x, and a pooled Team allowance (up to $500/month based on seat mix). Credits cover the Claude API, Managed Agents, the Agent SDK and the Playground, but not Claude Code or extra in-app usage, and unused credit expires every billing cycle with no rollover. This replaces the Agent SDK credit program announced in June, which Anthropic's own FAQ now says is no longer available.
Mistral put Large 4 (Le Chonk) into public preview on 2026-10-06. The official announcement and model card both list $1.36 input / $4.18 output per 1M tokens (cached input $0.14), but the actual billing page runs a straight 50% launch sale: $0.68 input / $2.09 output (cached $0.07). No end date is published anywhere. This is the second time this series has caught the same move — Gemini 4 Argon did it on 9/30. Weights and a named license are still due by end of month.
Claude Sonnet 4 (`anthropic.claude-sonnet-4-20250514-v1:0`) reaches End-of-Life on Amazon Bedrock today, a full 4 months after it retired on Anthropic's own Claude API (2026-06-15). Every call to it now fails outright. The recommended replacement, Claude Sonnet 4.6, costs exactly the same on the default global endpoint ($3 input / $15 output per MTok) — so migrating is free if you're not region-locked. But Sonnet 4.6 belongs to the post-4.5 generation, which carries a 10% premium on region-locked and multi-region endpoints — a line item Sonnet 4 never had. Migrate for compliance reasons and your bill quietly goes up 10%.