Two frontier models. One $100 subscription each. Snapshot 08 Sep 2026
Claude Fable 5.1 Claude Max 5x, $100/mo
vs
GPT-6 Astra ChatGPT Pro 5x, $100/mo

Same price, opposite strengths. One of them builds better, the other operates better, and neither company will tell you what your weekly limit actually is.

Point at a category to see what decided it.

4
categories to Fable
3
categories to Astra
1
even
0
weekly caps published
by either company

Edge is an editorial call on the published evidence, not a measurement. Hover or tap any category name for the reasoning; every figure behind it is sourced at the foot of the page.

Fable 4 Astra 3 Even 1
What $100 buys
Not scored
Not scored

What $100 buys

The models are the draw. The plans are how you get them, and they are shaped very differently.

Claude Max 5x
$100/mo, no annual billing
Structure
5× Pro per rolling 5-hour session, plus weekly caps. The 5× is a session multiplier, not a weekly one.
Pools
One. Chat, Claude Code, every subagent and Claude in Chrome all draw from the same meter.
Caps inside it
An Opus-only sub-cap, and Fable 5.1 capped at 50% of the weekly allowance. A ceiling in the same bucket, not extra room.
Getting Fable at all
Included here. On Pro at $20 it is not, so $100 is the entry price for Fable 5.1.
Effort
low → max, changeable mid-conversation without breaking the prompt cache.
Past the line
Pay-as-you-go usage credits.
Next change
14 Sep 2026: the +50% boost becomes a permanent +25%. Anthropic's own wording is a 17% reduction against today.
ChatGPT Pro 5x
$100/mo, launched 9 Apr 2026
Structure
5× Plus on a rolling 5-hour window, plus a weekly cap OpenAI has never put a number to.
Pools
Two. Chat is metered separately from Codex and ChatGPT Work, so research costs you no coding messages.
What each holds
Chat: 50 GPT-6 Pro messages a week. Codex and Work: 25–225 local messages per 5 hours.
Getting Astra at all
Included, but metered at half Sol's rate on every plan. Sol gets 50–500 per 5h where Astra gets 25–225.
Effort
low → max. Fast mode multiplies burn roughly 2.5×.
Past the line
Free banked resets, plus a purchasable instant weekly reset.
Recent change
Around 6–7 Sep, heavy users reported limits cut up to 4×. Never announced or confirmed.

OpenAI's $100 tier arrived in April 2026, after Codex crossed three million weekly users, offering 5× the Codex access of Plus at Anthropic's price point.

Fable takes it
Fable takes it

Quota and mileage

Neither company publishes a weekly token number. Both publish structure, and the structure differs far more than the shared price suggests.

Where your usage goes

One bucket against two. Most of the burn complaints on both platforms trace back to this.

Fable on Max 5x — one bucket
Claude chatClaude Code SubagentsClaude in Chrome
↓↓↓↓
Weekly allowance
All models, one meter, plus a 5-hour rolling window
Opus-only sub-cap
Fable 5.1 — at most 50% of the weekly total

Spend 70% on Opus and Sonnet and you hit the overall wall at 100%, even though Fable never touched its 50% share. Waiting out the 5-hour clock does not reset the weekly one.

Astra on Pro 5x — two buckets
ChatGPT chat
Chat pool
50 GPT-6 Pro messages per week
Codex CLIChatGPT Work Computer use
↓↓↓
Codex and Work pool
25–225 local messages / 5h, plus an unpublished weekly cap

The separation is real, but the chat pool is small. 50 messages a week is a handful of hard questions. Computer use lands in the coding pool, so it competes with your coding.

What users reported

Launch-week burn on both sides. Individual reports, not measured averages.

ModelPlanWhat happened
Fable 5.1Max 20xFull 5-hour quota gone in 52 minutes from a single prompt
Fable 5.1Max 20x45 minutes of coding across 3 chats took the 5-hour session and 38% of the weekly Fable allowance
Fable 5.1Max"Burns out the usage limits on Low effort within 5–10 minutes"
Fable 5.1MaxCap hit in 4 minutes on cache-heavy work; cache writes ran over 65% of real cost
AstraPro"Eats a full week in a day. The only thing keeping Codex usable is OpenAI handing out resets every 48 hours"
AstraPlus"One proper Astra prompt can use all of your 5 hour usage limit"

Fable's burn has a config fix

Subagents inherit the lead model by default. One prompt spawning nine Fable subagents is what produced the 52-minute figure. Pinning subagents to Sonnet 5 or Haiku 4.5 moves that fan-out off the expensive meter entirely.

Limit changes through 2026

Both companies are squeezing. Only one of them tells you in advance.

13–28 Mar 2026
Claude: temporary 2× off-peak usage. Ended.
9 Apr 2026
OpenAI launches the $100 Pro tier at 5× Plus.
6 May 2026
Claude: 5-hour limits doubled for Claude Code, peak-hour throttling removed.
13 May 2026
Claude: the +50% temporary weekly boost begins.
1 Sep 2026
Fable 5.1 ships. Anthropic resets all 5-hour and weekly limits the same day.
3 Sep 2026
Astra ships, metered at half Sol's rate.
5 Sep 2026
OpenAI credits every paid subscriber a full banked reset.
~6–7 Sep 2026
Heavy users report Astra limits cut up to 4×. Unannounced, unconfirmed.
7–8 Sep 2026
Another global reset across all paid plans.
13 Sep 2026
Claude: the +50% boost ends.
14 Sep 2026
Claude: permanent +25% replaces it, which Anthropic states as "a 17% reduction in weekly limits."

Both multipliers overstate weekly throughput

Anthropic's 5× and 20× apply to the 5-hour session, not the week. The Kahn v. Anthropic suit alleges real weekly throughput for Max 20x runs closer to 6–8× Pro. Treat that as an allegation, but treat the multiplier as a session number either way. OpenAI publishes no weekly number at all.

Community estimates

Reverse-engineered, not official. Included because they are the only per-plan figures in existence.

PlanPer 5 hoursPer weekConfidence
Claude Max 5x~225 messages~140–280 Sonnet-h, ~15–35 Opus-hestimate
Claude Max 20x~900 messagesnot publishedestimate
Pro $100, Astra25–225 local msgsnot publishedofficial range
Pro $100, Sol50–500 local msgsnot publishedofficial range
Plus $20, Astra5–45 local msgsnot publishedofficial range

What it means: Claude gives you a dated, quantified cut you can plan against. ChatGPT gives you a larger burst budget and free resets, but the number can move without notice. At $100 a month, a limit you can plan against is worth more than one that is occasionally larger.

Contested
Contested

Agentic coding

Closer than either launch post suggests. Astra takes the multi-step trajectory benchmarks; Fable takes patch accuracy and the one neutral composite.

Coding benchmarks, score out of 100
Higher is better. Vendor-published except the Coding Agent Index, which is Artificial Analysis's independent composite of Deep SWE, Terminal-Bench and repository QA.
Fable 5.1Astra

Fable-only results

LiveCodeBench 90.52%, CursorBench 3.2.0 73.4% up from 70.5%, and Terminal-Bench-Science 52.6%, more than double Fable 5's 24.7%. OpenAI has published no matched figures for these.

The counter-evidence

One tester's 15 real-world use cases scored Astra 10 wins to Fable's 5. Astra also finished tasks on ~21K tokens where Fable used ~64K.

What it means: repo-scale refactors and correct patches favour Fable's SWE-bench Verified 95.0% and the neutral composite. Long autonomous terminal trajectories favour Astra's DeepSWE and Terminal-Bench wins. Nobody should switch a $100 subscription over a 3-point composite gap.

Fable takes it
Fable takes it

Design and UI

The most one-sided category on this page, and the only one with no numbers behind it at all.

No controlled test exists

Every design comparison published so far is an uncontrolled hands-on. Nobody has run identical prompts side by side under matched conditions. What follows is consensus from repeated independent testing, not measurement.

Fable 5.1
Wins application interfaces

One-shots polished, custom UI. Repeatedly called the best design model available. Strongest where work is iterated toward a finished product.

Weakness: slower to a good first draft on marketing pages. Needs iteration where Astra sometimes does not.

Astra
Wins one-shot landing pages

Real layering and parallax depth rather than flat AI output. One tester found its first attempt matched a Fable design refined over ~15 iterations. Also handles multimodal editing.

Weakness: a recurring green-tinted card-and-grid look, and a tendency to turn any request into a landing page. A taste failure, which more quota does not fix.

What it means: if design means a marketing site you generate once, Astra is competitive and faster. If it means an application interface you will refine, Fable is the stronger choice, and the gap here is the widest on the page.

Astra takes it
Astra takes it

Computer use

Astra's clearest win, though smaller than the coverage implies. Most of the numbers quoted as a head-to-head are not one.

AutomationBench — the one clean head-to-head
Zapier's benchmark: 657 tasks across six business domains, 47 simulated SaaS tools, strict programmatic pass/fail. Both vendors published on it.
AnthropicOpenAI

10 points absolute, about 32% relative. That is the honest size of Astra's measured advantage on computer use.

OSWorld 2.0 is not a comparison

You will see "Astra 72.6% against Fable 77.9%" quoted as a ranking. It is not one. The two labs ran different task releases with different scoring conventions, and Fable 5.1 was never run on OpenAI's row. One tracker puts it plainly: do not mix harnesses; 72.6% and 77.9% are not one ranking.

BenchmarkAstraFable 5.1Comparable?
AutomationBench41.4%31.4%yes
OSWorld 2.072.6%77.9% / 41.7%different harness
ScreenSpot-Pro92.7%not publishedno Fable figure
BrowseComp91.5%not publishedno Fable figure
OSWorld time per task~40 minnot publishedvs Sol's ~75 min
Mind2Web speed1.9× fasternot publishedvs Sol setup

Part of the speed win is harness, not model

OpenAI's computer-use harness rewrite sped up GPT-5.6 Sol by roughly 60% as well. "Astra is 2× faster" bundles engineering that would have helped any model.

The architecture difference

This drives more real-world frustration than the benchmark gap does.

Claude in Chrome
Drives your local browser

An extension driving your own Chrome through the debugger API: your profile, your cookies, your logged-in sessions.

Documented failures: persistent connection failure from the Claude Code CLI; Claude Desktop's Cowork silently breaking Claude Code's Chrome integration and the reverse; a failed bridge at startup killing the connection for the whole session; reports of it moving very slowly; Chrome crashes; a prompt-injection vulnerability below v1.0.41.

Model by plan: Pro gets Haiku only. Max and above can point it at Opus or Sonnet. Browser work is more compute-intensive than chat, so it eats more of your limit.

OpenAI after Atlas
Drives a cloud browser

Atlas was killed around 9 Aug 2026. OpenAI's stated reasoning: the browser is a feature, not the destination. Its parts split three ways: page Q&A into a Chrome extension, logins and downloads into the desktop app, and the agent itself onto a remote cloud browser on OpenAI's servers.

Upside: no local Chrome to crash, no debugger bridge to fail, no two products fighting over one browser. That entire class of failure does not exist.

Downside: it is not your browser. Astra runs credential-blind, driving an authenticated session without login details entering its context, but it pauses for approval at login walls and before consequential actions.

What it means: Astra is measurably better at business-workflow automation and substantially faster. If your frustration is capability, that is a real 10-point gain. If your frustration is plumbing, the cloud-browser architecture is the bigger win. Both platforms charge computer use against your coding budget; neither gives it a separate allowance.

Even
Even

Security auditing

If you avoided Claude because it refused security work, that was Fable 5. It was fixed on 1 September.

What changed between Fable 5 and 5.1

Fable 5's cyber classifier keyed on security-adjacent vocabulary rather than intent. It flagged systems programming terms, cloud reliability language, and the literal phrase "code review". Defensive vulnerability discovery was blocked at 90.0%. In Fable 5.1 that dropped to 7.0%, with roughly 60% fewer classifier interventions per session.

What each model allows

Both columns are hands-on test results, not policy documents. Fable tested against a deliberately broken PHP login handler; Astra tested via API against vulnerable PHP the testers owned.

TaskFable 5.1Astra
Source-code vulnerability reviewallowed, full modelallowed
Patch and remediationallowedallowed
Regression test for the fixallowedallowed
Detection rule authoringallowedallowed
Defensive hardeningno downgradeallowed
Penetration testingfalls back to Opus 4.8Daybreak Blue
Compiled binary analysisfalls back to Opus 4.8Daybreak Blue
Proof-of-concept exploitfalls back to Opus 4.8refused, HTTP 400

Astra's block fires at the classifier before the model sees the prompt. Stating authorisation and retrying unchanged made no difference. The classifier keys on task shape, not declared intent.

The failure modes are opposite, and it matters

Fable silently downgrades to Opus 4.8 under a banner. In a long agent run the substitution can pass unnoticed, and mid-response flags bill at dual-model rates. Astra hard-fails. For automated auditing the hard fail is safer: a silent quality downgrade halfway through a security audit is exactly the failure you do not want in a security audit.

Offensive capability — read the caveat first
These measure turning vulnerabilities into working exploits. The shipping models refuse this work. Vendor-published and pre-mitigation, so they describe latent capability, not what a subscriber gets.
Fable 5.1Astra

Fable's fallback is the weak point

Its own system card shows every successful prompt-injection attack against Fable 5.1 was an attack on the fallback model. In browser automated mode, 21 of 29 successful attacks hit fallback models. The downgrade path is also the security-weak path.

Neither gate opens for $100

OpenAI's advanced cyber capability is off by default and needs an enterprise admin. Daybreak Blue covers defensive workflows and Daybreak Red covers exploit development; one team applied in July and had no decision seven weeks later. Anthropic gates Mythos 5.1 the same way.

Claude ships a security command; use it carefully

Claude Code has /security-review built in for SQLi, XSS, auth flaws, insecure data handling and dependency vulnerabilities. The GitHub Action variant is explicitly not hardened against prompt injection, under CVE-2025-59536, arbitrary code execution via injection in PR content. Trusted PRs only.

What it means: auditing and repairing vulnerabilities in your own source works on both, today, on the standard plans. Astra has the better raw ability and the more honest failure mode; Fable has the better workflow integration and needs no gate for source review. This is a tie, and it should not decide your purchase.

Worth knowing on either platform: a study of 2,390 prompts from the National Collegiate Cyber Defense Competition found safety-aligned models refuse defensive requests carrying security terminology at 2.72× the rate of neutral ones. It also found that stating you were authorised made refusals go up, because the model read the claim as a warning sign.

Astra takes it
Astra takes it

Token efficiency

Identical list prices, very different consumption, and one cache detail that partly cancels Astra's lead once you are on a subscription rather than an API bill.

Per million tokensFable 5.1Astra
Input$10.00$10.00
Output$50.00$50.00
Cache reads$0.25, cut 75% in 5.1not published at parity
Fast mode~2.5× multiplier
Effort levelslow → max, mid-conversationlow → max
Tokens consumed per task
Single tester, matched task. Lower is better.
Fable 5.1Astra
Cost across a full test suite
Lower is better. Not like-for-like: Astra ran at Ultra Thinking, Fable did not.
Fable 5.1Astra

The cache detail that cuts the other way

Over 90% of tokens in a heavy Claude Code session are cache reads. Fable 5.1 cut those 75% to $0.25/M, and on a Max subscription they are included flat. Anthropic's estimate is 25% cheaper than Fable 5 for typical work, up to 45% for highly agentic work. Astra's raw efficiency is real, but it pays the same $10/$50 list with a 2.5× Fast-mode multiplier available to make it worse.

What it means: Astra is materially more token-efficient and stretches a fixed quota further. On identical benchmark tasks Claude Code used 4× more tokens, and a matched task ran $2.50 against $2.04, a 23% delta. Fable's spend buys thoroughness rather than waste, but you pay for it. On subscriptions the cache pricing narrows the gap more than the token counts suggest.

Fable takes it
Fable takes it

Subagents

Both delegate to cheaper models with their own reasoning effort. Only one lets the cheap tier escape the expensive meter.

Claude Code
Delegates to Sonnet 5 and Haiku 4.5

The advantage: those models sit outside the Fable 50% weekly sub-cap. The token fan-out that kills people lands on the cheap meter, not the expensive one.

The trap: subagents inherit the lead model by default. Leave that unset and nine Fable subagents spawn from one prompt, the documented cause of the 52-minute quota wipe. Set model explicitly.

Codex
Delegates to sol, terra and luna

The controls: per-agent model_reasoning_effort from low through ultra. Cleaner ergonomics than Claude's; this is a first-class API.

The limitation: everything shares one Codex pool, metered at Astra's halved rate. There is no cheap meter to move the fan-out onto.

Fan-out is expensive on both

Anthropic's own documentation puts multi-agent workflows at roughly 4–7× the tokens of a single-agent session, with Agent Teams around 15×. OpenAI's docs are blunter: subagent workflows consume more tokens than comparable single-agent runs. Neither platform makes delegation free; Claude gives you somewhere cheaper to put it.

Which one to buy

Both are month-to-month with no annual lock. Switching costs you a month, not a year.

Buy Fable if
You do heavy agentic coding alongside design or UI work.
You build application interfaces you will refine, not generate once.
You want to know in advance when your limits change.
You orchestrate at low or medium effort and delegate to cheap subagents.
Buy Astra if
Browser or desktop automation is a real share of your week.
You need control of desktop apps: spreadsheets, CAD, video editors.
More than about 40% of your usage is non-coding chat and research.
You want voice, image generation, Sora and the wider product surface.
Buy neither if
You only audit and patch your own source. Genuine tie; either plan does it.
You need binary or malware analysis. Both gate it behind programmes a $100 subscriber will not get into.
You mostly chat and rarely hit limits. Stay on the $20 tier.
You run high or xhigh effort constantly. Neither $100 plan holds. That is a $200 conversation.

Making $100 last, either way

On Fable: pin subagent models rather than inheriting; run the orchestrator at low and escalate per message, which preserves the cache; clear between unrelated tasks; keep CLAUDE.md short; watch both the all-model bar and the Fable bar, since they hit independently. On Astra: start at medium reasoning and escalate only on conflicting evidence; avoid Fast mode by default; bound task scope before starting; route triage to terra and luna.

What can't be verified

Every gap in the evidence behind this page, listed.

ClaimStatus
Weekly token or message caps for either $100 planneither company publishes one
OSWorld 2.0 as an Astra-vs-Fable rankinginvalid, different harnesses
Fable 5.1's ScreenSpot-Pro scorenever published
"Astra 95% vs Fable 40% on robot control"unsourced social claim, ignore
The ~4× Astra limit cut of 6–7 Sepuser reports only, unconfirmed
Design comparisonsall uncontrolled hands-on
Max 20x real weekly throughput at 6–8× Prolitigation allegation, untested
Community per-plan hour estimatesreverse-engineered
Most benchmark scoresvendor-published; exceptions are Artificial Analysis and Irregular
ExploitBench and ExploitGym figurespre-mitigation; the shipping models refuse this work

Everything here reflects 8 September 2026. Claude's limits change on the 14th. OpenAI's have moved twice in the past week. Check the date before you trust the page.

Sources

Anthropic — Introducing Claude Fable 5.1 and Mythos 5.1 Claude Help — Fable models on your plan Claude Help — Models, usage and limits in Claude Code Claude Help — Automated security reviews in Claude Code Claude Help — Claude in Chrome troubleshooting BleepingComputer — Claude Code weekly limits cut 17% explainX — Claude usage limits 2026 timeline Developers Digest — Claude usage limits and Fable burn rates AI Free API — the Fable 50% rule claude-code issue #24593 — Chrome extension won't connect Zvi Mowshowitz — Fable 5.1 and Mythos 5.1 system card StationX — Fable 5.1: still a security nightmare? StationX — GPT-6 Astra: we tested what it refuses Digital Applied — Claude's safety classifier and coding tradeoffs Cerbos — Fable 5 and Sol authorization refusals TechCrunch — ChatGPT's $100/month Pro plan TNW — OpenAI's $100 Pro plan targets Claude Max The Decoder — Astra at half the rate of Sol codexusage.dev — Astra Codex usage limits Codex Docs — Subagents explainX — Astra usage limits cut 4× AI Catchup — Astra long-tail usage improvements MacObserver — OpenAI resets Astra usage limits AtlasCloud — why Astra usage disappears Vellum — Astra benchmarks explained DataCamp — Astra vs Fable 5.1 DataCamp — Fable 5.1 features and benchmarks USTech — OSWorld latency, and why the numbers don't mix Miraflow — OSWorld 2.0 explained Zapier — AutomationBench Artificial Analysis — AutomationBench-AA MindStudio — Astra vs Fable for web design MindStudio — what they cost to run TechCrunch — OpenAI shutting down Atlas OpenAI Help — Evolving Atlas into ChatGPT OpenAI Help — Daybreak trusted access for cyber The Hacker News — Astra 100% on ExploitBench CSO Online — Astra crosses the critical cyber threshold OpenAI — Safety overview: GPT-6 Astra CloudZero — Codex vs Claude Code Christopher Alarcon — paying for both Aiden Scott on X — 45 minutes, 38% of weekly Fable Naman Goyal on X — low effort burns out in 5–10 minutes BridgeMind on X — "eats a full week in a day" Kai on X — published Astra limits ClaudeDevs on X — limits reset with Fable 5.1