Last updated: May 15, 2026. We update this tracker as new information emerges. Bookmark it.
MAY 2026 UPDATE — Spud shipped, but as GPT-5.5. OpenAI announced GPT-5.5 (codename “Spud”) on April 23, 2026 at 10am PT — rolled out same-day to Plus, Pro, Business, and Enterprise in ChatGPT, then API on April 24. GPT-5.5 Instant became the free-tier default on May 5. GPT-5.5 Pro and GPT-5.5 Thinking shipped alongside the standard variant. Benchmarks: 88.7% SWE-bench Verified, 82.7% Terminal-Bench 2.0 (~13 points ahead of Claude Opus 4.7). The tracker below is preserved as a historical record; jump to “What Actually Happened” for the resolution and what to watch for next (hint: GPT-5.6 is in internal testing and the real GPT-6 is now a Q3-Q4 2026 base case).
It’s now been a full week since the fabled April 14 launch. Still no Altman tweet, still no blog post, still no GPT-6. But OpenAI hasn’t been completely silent — in the days on either side of April 14, the company shipped GPT-5.4-Cyber (a security-tuned variant for vetted researchers), GPT-Rosalind (a biology-specialized reasoning model), and a major Codex upgrade (more agentic, plugins, multimodal). Just not Spud.
Meanwhile, Anthropic ate the week. Claude Opus 4.7 shipped April 16 with SWE-bench Verified at 87.6% and wide cloud availability. Claude Design shipped April 17 — the AI prompt-to-prototype tool that Figma and Adobe stocks pre-reacted to. OpenAI is losing the “best frontier model” narrative in real time.
The numbers tell the story. Polymarket’s “GPT-6 by June 30” contract has collapsed from ~93% a week ago to roughly 45% today. Traders aren’t betting on May anymore — they’re pricing a Q3 launch as the new base case. A separate “GPT-5.5 released by April 23” market is still showing around 83%, which is the most concrete near-term signal anyone is willing to put money on.
Here’s what we actually know as of April 21.
What Actually Happened — Spud Shipped as GPT-5.5
Two days after this tracker last updated, OpenAI ended the suspense. On April 23, 2026 at 10am Pacific, the model everyone was calling “GPT-6” launched — as GPT-5.5. Codename Spud was real. The 40% performance delta was overstated. The “unified super-app” rumor was hype. But Spud itself? Real, shipped, and now sitting at the top of two of the three benchmarks that matter most.
The launch in one table:
| Variant | ChatGPT | API | Audience |
|---|---|---|---|
| GPT-5.5 (standard) | Apr 23, 2026 | Apr 24, 2026 | Plus, Pro, Business, Enterprise |
| GPT-5.5 Thinking | Apr 23, 2026 | Apr 24, 2026 | Same tiers as standard |
| GPT-5.5 Pro | Apr 23, 2026 | Apr 24, 2026 | Pro / Business / Enterprise |
| GPT-5.5 Instant | — | — (ChatGPT UI only) | Free tier as default, May 5, 2026 |
| GPT-5.5-Cyber | — | Limited (Trusted Access) | Vetted cyber researchers, May 7, 2026 |
The benchmarks that matter (and where Spud actually wins):
| Benchmark | GPT-5.5 | GPT-5.4 | Claude Opus 4.7 | Notes |
|---|---|---|---|---|
| Terminal-Bench 2.0 (agentic tool use) | 82.7% | 75.1% | 69.4% | New state-of-the-art, ~13 points ahead of Opus |
| SWE-bench Verified (coding) | 88.7% | 87.6% | 87.6% | Modest gain, narrowest lead |
| SWE-bench Pro (multi-file coding) | 58.6% | 57.7% | — | Still room for competitors |
| MMLU (general knowledge) | ~92.4% | ~90% | — | Marginal |
| OSWorld-Verified (computer use) | 78.7% | — | 78.0% | Statistical tie with Opus |
| FrontierMath (Tiers 1-3) | 51.7% | — | 43.8% | Meaningful lead |
| ARC-AGI-2 | +11.7 over 5.4 | baseline | — | Biggest single-benchmark jump |
What’s actually new vs GPT-5.4 (per the system card and early reviews):
- Long-context reliability, not capacity. Context window only bumped from 1.0M to 1.05M tokens, but constraints persistence and on-topic behavior at 512K-1M is described as a “step change” by independent reviewers. The win is in using the window, not its size.
- Stronger agentic / tool use. The Terminal-Bench 2.0 lead reflects fewer early-exits, better multi-step orchestration, and more reliable browser/terminal navigation. Cursor’s CEO publicly called it “noticeably more persistent than 5.4.”
- Better abstract and scientific reasoning. GeneBench jumped 19% → 25%, BixBench 74% → ~80.5%, FrontierMath solid lead over Opus 4.7.
- First system card with a top-level “Alignment” section. Severity-3 misalignment rate ~0.01%, no severity-4 events observed. (Read: OpenAI is foregrounding alignment work as the conversation around frontier safety heats up.)
- Same per-token latency as 5.4 at higher capability. OpenAI claims many Codex tasks now finish in fewer tokens due to better planning — so effective cost can be lower despite the higher list price.
API pricing (per million tokens, short-context):
| Model | Input | Cached Input | Output | Notes |
|---|---|---|---|---|
| gpt-5.5 | $5.00 | $0.50 | $30.00 | Frontier, 1.05M ctx |
| gpt-5.5-pro | $30.00 | — | $180.00 | Higher test-time compute |
| gpt-5.4 | $2.50 | — | $15.00 | Prior frontier (1.0M ctx) |
| gpt-5.4-mini | $0.75 | — | $4.50 | Smaller, cheaper |
| gpt-5.4-nano | $0.20 | — | $1.25 | Tiny, cheapest |
Long-context (>272K tokens) pricing kicks in a 2× input / 1.5× output multiplier on the full session. Batch and Flex tiers are 50% off list, Priority is 2.5× list — same structure as the rest of OpenAI’s API. GPT-5.5 Instant has no standalone API SKU — it’s exposed only through ChatGPT’s free tier and the internal real-time router.
The naming surprise. Polymarket’s “GPT-5.5 by April 23” market resolved YES at ~83% pre-launch — the prediction-market signal beat the “GPT-6 by June 30” market by a mile. OpenAI is clearly committing to the rapid 5.x cadence (5.4 → 5.5 → likely 5.6) rather than another big-number leap. Brockman’s “two years of research, not incremental” framing was about the underlying training, not the version number.
Official sources: Introducing GPT-5.5 — OpenAI, GPT-5.5 System Card, GPT-5.5 Instant System Card, Deployment Safety Hub.
The Quick Answer
| Question | Answer |
|---|---|
| Is GPT-6 out yet? | No (as of April 21, 2026) |
| Did anything ship on April 14? | Nothing at the GPT-6 scale. Rumor fully busted. |
| What did ship mid-April? | GPT-5.4-Cyber (Apr 14), GPT-Rosalind (Apr 16), Codex upgrade (Apr 16) |
| Has Altman said anything since? | No new GPT-6/Spud tweet in the April 17–21 window. |
| What did OpenAI confirm? | Pretraining finished March 24, 2026. Nothing about a date since. |
| Will it be called “GPT-6” or “GPT-5.5”? | Polymarket is leaning GPT-5.5 — “GPT-5.5 by Apr 23” market at ~83% |
| Codename? | Spud 🥔 |
| Polymarket “GPT-6 by June 30” | ~45% (collapsed from ~93% on Apr 13) |
| Polymarket by Sep 30 / Dec 31 | ~72% / ~86% |
| Most likely window now | Late April to Q3 2026 |
The Story So Far — Visualized
Three weeks, three milestones, one launch that didn’t happen. Here’s how the Spud saga has played out since pretraining finished.
What OpenAI Has Officially Confirmed
Three things, nothing more:
- Pretraining for “Spud” finished March 24, 2026. Sam Altman confirmed this directly on X.
- Altman said launch is “a few weeks” away (as of March 24 — so the clock started ticking three and a half weeks ago).
- Brockman called Spud “two years of research” and “not an incremental improvement” in public interviews.
That’s it. No official date, no model card, no API announcement, no teaser video. OpenAI has not published a blog post, a press release, or a product page for GPT-6.
The Pressure Map — Why Every Day Without Spud Hurts OpenAI
OpenAI isn’t launching into an empty field. Every major competitor has already shipped in April, or is shipping this week. The longer Spud sits in the cooker, the more of the “frontier model” narrative gets eaten.
At the HumanX conference two weeks ago, the dominant narrative was “Claude Mania” — not OpenAI, not GPT-6. With Opus 4.7 now shipped and Claude Design live, Anthropic just locked in a second consecutive launch cycle where they own the frontier-model story.
That pressure explains the April 14–16 side-launches. GPT-5.4-Cyber, GPT-Rosalind, and a Codex upgrade are real work — but none of them is Spud. They’re holdover content to fill the news cycle while the flagship stays in safety review. Altman can’t pre-announce without blowing the launch arc. But he also can’t let Claude own the narrative two months running.
The April 14 Rumor: A Postmortem
Worth revisiting now that it’s a confirmed miss:
The original source: An unverified “insider” leak posted to a smaller blog on April 7. The leak claimed:
- April 14 launch alongside a “unified super-app” (ChatGPT + Codex + Atlas)
- ~40% performance improvement over GPT-5.4
- 2M-token context window
Why it fell apart:
- The source had no verifiable track record
- “40%” and “2M” are suspiciously round marketing numbers
- OpenAI historically launches with zero advance notice — a 6-day heads-up would be a first
- No corroboration from TechCrunch, The Verge, The Information
- Three days past the claimed date with no Altman activity = confirmed false
What was real: The insider teases from @thsottiaux (“next week will be about more than cooking”) and @pashmerepat (“things are about to get wild ❄️”) on April 10-11 were real tweets from real OpenAI employees. But “next week” in OpenAI-speak has always meant a window, not a day. The April 14 date was bolted on by the leaker.
Verdict: The broader “mid-April to early May” window is still supported. The specific April 14 date was never credible.
Polymarket Odds (Updated April 21)
The market has repriced hard since April 17. Traders aren’t just acknowledging the April 14 miss anymore — they’re pulling probability mass out of Q2 entirely and moving it into Q3 and Q4.
| Market | Probability |
|---|---|
| “GPT-6 released by June 30” | ~45% (was ~93% on Apr 13 — collapsed) |
| “GPT-6 released by September 30” | ~72% |
| “GPT-6 released by December 31” | ~86% |
| “GPT-5.5 released by April 23” (separate market) | ~83% |
| Manifold “GPT-6 by May 15” | ~40% (was ~82% on Apr 13) |
| PredictionPulse | ~28% by June 30 (the stubborn skeptic) |
Two readings of this: traders either expect an imminent GPT-5.5 drop this week followed by GPT-6 in Q3, or they think the flagship has genuinely slipped. The gap between “by June 30” (45%) and “by Dec 31” (86%) is wide — the market is now pricing a real possibility of a multi-month slip, not a few-week delay.
Will It Be “GPT-6” or “GPT-5.5”?
Still genuinely undecided. The naming split from two weeks ago hasn’t resolved:
Signals pointing to “GPT-5.5”:
- Insiders on X keep using “GPT-5.5” more than “GPT-6”
- Daniel Mac (tech reporter, 1,141 likes): “GPT-5.5 aka Spud 🥔. OpenAI’s best model yet.”
- OpenAI history: half-numbers signal “major improvement, not paradigm shift”
Signals pointing to “GPT-6”:
- Brockman’s “two years of research” framing
- Rumored unified product ecosystem launch (ChatGPT + Codex + Atlas)
- If the 40% performance delta is real, the marketing team will want the bigger number
Our read: Naming will be decided at launch based on benchmark performance. If Spud clears GPT-5.4 by 25%+ on coding and reasoning benchmarks, it’s “GPT-6.” If it’s 10-15%, it’s “GPT-5.5.” The naming decision tells us how confident OpenAI is.
What’s Expected (Leaked, Not Confirmed)
These come from multiple leaks and aggregator analysis. None are officially confirmed. We’ve seen no new leaks in the 72 hours since April 14, which actually increases our confidence that the previous leaks were speculation, not insider info.
Architecture:
- Trillions of parameters, Mixture-of-Experts (MoE) style
- Training on 100,000+ H100/H200-class GPUs at OpenAI’s Stargate cluster (Abilene, Texas)
- Major scale-up over GPT-5.x
Context & modality:
- 1M-2M token context window (vs 128K for GPT-5.4)
- Native multimodal (text, image, improved audio/video)
- Altman has been telegraphing persistent memory for months as the headline feature — not raw reasoning gains
Performance:
- Rumored ~40% improvement on coding, reasoning, agent benchmarks
- Expected to retake lead on Chatbot Arena
Agentic features:
- Multi-step planning, tool orchestration, browser navigation
- Ties into the “Atlas” AI-native browser
- May unify ChatGPT + Codex + Atlas into a single “super app”
Safety:
- Tightened jailbreak resistance
- Enterprise-grade policy tooling
- Granular admin controls
Treat all of this as 55-65% confidence. Official specs will differ at launch.
While You Wait — Here’s What Actually Matters
Whether Spud launches April 21 or May 25, the users who actually benefit from GPT-6 aren’t the ones refreshing launch-day Twitter. They’re the ones who already know how to talk to AI. A better model with lazy prompts still gives you generic answers. A mediocre model in skilled hands ships production code.
The skill that makes any GPT-6 user 10× better is prompt engineering plus an actual AI workflow — and you can learn it in 2 hours today, not 2 months after Spud drops.
- Prompt Engineering (free to try) — 8 lessons, ~90 minutes. The techniques that separate power users from people typing “write me an email.”
- AI Fundamentals (free to try) — The mental model for how these systems actually work, so GPT-6’s new features make sense on day one instead of week three.
First 2 lessons of each are free with an account. No credit card; 30 seconds to sign up. If Spud ships tomorrow, you’ll be the person on your team who knows what to actually do with it.
What to Watch Next (Updated May 15)
The April 21 framing of this section is preserved below for historical record. As of mid-May, here’s the actual forward-look:
The market repriced when Spud shipped as 5.5. Polymarket and Manifold both pulled probability mass forward from “GPT-6 by June 30” (because no one expects another flagship in six weeks) and backward from “GPT-6 by Dec 31” (because the 5.x cadence makes a true 6 less urgent). Current numbers as of May 15:
| Market | Probability | Movement since April 21 |
|---|---|---|
| Polymarket — GPT-6 by June 30, 2026 | ~10-11% | Down from ~45% — the April 23 GPT-5.5 launch killed near-term odds |
| Polymarket — GPT-6 by September 30 | ~55-60% | Down from ~72% |
| Polymarket — GPT-6 by December 31 | ~82% | Roughly flat |
| Manifold — GPT-6 before June 2026 | ~3% | New |
| Manifold — GPT-6 before September 2026 | ~51% | New |
| Manifold — GPT-6 before December 2026 | ~71% | New |
| Manifold — “GPT-6 in 2026?” (explicit naming) | ~65% Yes | New |
Translation: traders now think the real GPT-6 lands in Q3-Q4 2026, with December as the modal landing point. About ~28% probability is now in 2027 or later, which is a meaningful tail risk if you’re planning product roadmaps.
The near-term watchlist:
| Window | What to watch for |
|---|---|
| May 19-20 | Google I/O keynote — pricing/model announcements that pressure OpenAI’s next move. |
| Late May - June | GPT-5.6 internal testing per market chatter. Polymarket on a 5.6 market shows ~88% near-term odds. Expect a quiet drop. |
| June - August | Watch for an Altman X post or OpenAI DevDay (typically Q3) telegraphing the real GPT-6 timeline. He’s joked publicly about training “GPT-6 with extra goblins” (referencing a Codex bug) — that’s the signal he’s actively working on it, but no hard date. |
| September | The new mass-of-probability landing point per both Polymarket and Manifold. If the next year shapes like 5.4 → 5.5 → 5.6, this is when a true GPT-6 needs to differentiate itself from the 5.x line. |
| End of 2026 | If GPT-6 still isn’t out, the “OpenAI got out-shipped on naming, not capability” narrative crystallizes. Polymarket has 82% odds it ships by then — bet against that line if you’re a contrarian. |
If you’re hitting F5 on OpenAI’s blog right now, slow down. The pattern from the last four OpenAI launches (including GPT-5.5): no advance date, Altman tweet drops same day, blog post 30 minutes later, API access rolls out over 24-48 hours.
Archived: April 21 watchlist
For the historical record, here’s what we were watching three weeks ago:
| Date range | What we were watching |
|---|---|
| Apr 22-23 | Polymarket had GPT-5.5 at ~83% for April 23. Resolved YES. Spud dropped as 5.5. |
| Apr 24-30 | API launch (Apr 24, confirmed). |
| May 1-31 | GPT-5.5 Instant rollout to free tier (May 5, confirmed). GPT-5.5-Cyber for vetted researchers (May 7). |
What This Means for You (Updated for May 2026)
If you’re a developer: GPT-5.5 is now the model to evaluate, not the future GPT-6. Real numbers: $5/$30 input/output per 1M tokens (short context), 1.05M context window, state-of-the-art on Terminal-Bench 2.0. If you’re building agentic workflows, this is the strongest model on the market today — including against Claude Opus 4.7, which still leads on raw coding judgement and now plays catch-up on agent tooling. The actual GPT-6 migration question is on hold until Q3-Q4 2026.
If you’re building AI products: The Q1 anxiety about “what if GPT-6 ships and we look stale” is now mostly resolved. The 5.5 generation is here, you can build against it, and you have ~5-7 months before the real GPT-6 question becomes pressing again. Use the time to ship — switching costs to GPT-6 will still be low (same API surface, marginally better numbers), and trying to architect ahead of unconfirmed specs is a known time-sink.
If you’re choosing between AI tools: GPT-5.5 and Claude Opus 4.7 are now both at-the-frontier with different strengths — Opus 4.7 still wins on raw coding judgement and instruction-following, GPT-5.5 wins on terminal/agentic and FrontierMath. Pick based on your workload. Gemini 3.1 Pro is the price-leader for high-volume work. There is no “wait for the next model” story right now; the next models came.
If you’re just curious: Spud is out. The question for the next six months isn’t “when does GPT-6 ship” — it’s “what does OpenAI call the next big jump, and does it ship before Anthropic ships Opus 5?”
The Bottom Line (Resolved, May 15)
The honest version of what we know in May 2026:
Spud shipped — as GPT-5.5, on April 23. The “GPT-5.5 by April 23” prediction market called it perfectly while the “GPT-6 by June 30” market got it wrong by ~50 percentage points. That tells you something important about which leaks to trust: real-money concentrated markets > insider blog rumors > X “I have a friend” claims. Always.
The real GPT-6 is now a Q3-Q4 2026 base case. Polymarket has it at ~10% by June 30, ~55-60% by September 30, ~82% by December 31. Manifold is more pessimistic in the near term (~3% before June, ~51% before September). About a quarter of probability mass is now in 2027 or later — a tail you should account for if your product roadmap genuinely depends on GPT-6 features.
GPT-5.6 is in internal testing. A Polymarket on the 5.6 release shows ~88% near-term odds. The 5.x cadence is real and faster than anyone expected. If you’re building, build against 5.5 today and assume incremental upgrades, not a paradigm leap, for the rest of 2026.
Anthropic vs OpenAI is now genuinely at par. Claude Opus 4.7 leads on coding judgement and instruction-following. GPT-5.5 leads on agentic / terminal benchmarks (~13 points on Terminal-Bench 2.0). Gemini 3.1 Pro is still the price-leader. There is no “wait for the next model” play right now — the next models are here and the lead is genuinely contested.
The lesson from the April 14 hype cycle is still the most useful takeaway: the next “insider” leak with a specific date and “40% performance improvement” round-numbered claim probably also won’t check out. OpenAI announces same-day, on Altman’s X, with a blog post 30 minutes later. That’s it. Nothing else is signal.
We’ll keep this page updated as the real GPT-6 picture clarifies through the summer.
Don’t wait on Spud — get ahead of it. Whether GPT-6 lands tomorrow or in July, the techniques that make these models actually useful are the same ones that already work today. Our AI Fundamentals course gets you the mental model in an afternoon, and Prompt Engineering teaches the skill that separates power users from people typing “write me an email.” Free to start, Pro for the full path. So when GPT-6 finally drops, you’ll know exactly how to get value from it on day one — instead of week three.
Related: If GPT-6 ships with agentic features as rumored, see our Claude vs ChatGPT 2026 comparison for context on how it stacks up. And the Claude Mania narrative explains why OpenAI is under so much pressure.
Sources:
Primary (OpenAI / official):
- Introducing GPT-5.5 — OpenAI
- GPT-5.5 Instant: smarter, clearer, and more personalized — OpenAI
- GPT-5.5 System Card — OpenAI
- GPT-5.5 Instant System Card — OpenAI
- Deployment Safety Hub — GPT-5.5
Coverage (April 23 launch and after):
- GPT-5.5 — Wikipedia
- OpenAI announces GPT-5.5 — CNBC, April 23, 2026
- OpenAI releases GPT-5.5, bringing company one step closer to an AI ‘super app’ — TechCrunch
- OpenAI releases GPT-5.5 Instant, a new default model for ChatGPT — TechCrunch, May 5
- GPT-5.5 Instant: fewer gratuitous emojis — 9to5Mac
Prediction markets (current pricing):
- Polymarket — GPT-6 Released by…?
- Manifold — When will OpenAI release GPT-6?
- Polymarket — OpenAI Predictions Overview
Tracker / analysis:
