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Model Comparison

GPT-6 Astra vs GPT-6.1 Terra

GPT-6 Astra (max) leads GPT-6.1 Terra (max) by 231 Elo, and their 95% ranges sit 151 Elo apart. Among 84 models, each ranked by its best configuration, GPT-6 Astra is #12 and GPT-6.1 Terra is #23. Cost per script: $1.15 for GPT-6 Astra (max) and $0.079 for GPT-6.1 Terra (max).

Last updated , from board data generated at 20:15 UTC.

GPT-6 Astra
2154 Writing Elo of GPT-6 Astra (max), its best configuration#12 of 84 models · 82.3/100 Writing Score · $1.15 per script2 configurations on the board
GPT-6.1 Terra
1923 Writing Elo of GPT-6.1 Terra (max), its best configuration#23 of 84 models · 80.3/100 Writing Score · $0.079 per script5 configurations on the board

Picks and Verdict

PickGPT-6 Astra

GPT-6 Astra (max)

Pick GPT-6 Astra (max) for the script you'll film when cost doesn't matter, since it leads Terra's best by 231 Elo and on all nine metrics at $1.15 a script.

PickGPT-6.1 Terra

GPT-6.1 Terra (low)

Pick GPT-6.1 Terra (low) for everything else, since its individual Elo range overlaps GPT-6 Astra (medium) and it costs $0.027 a script against $0.262.

GPT-6 Astra at max writes the better script, and it charges for it. GPT-6 Astra (max) leads GPT-6.1 Terra (max) by 231 Elo with 95% ranges 151 apart, the #12 model of 84 against the #23 model, and it's ahead on all nine metrics and all ten scripts, most on length and tone, by about four points each. It also costs $1.15 a script and takes 9.2 minutes, about 15 times Terra's price at max. Astra's thinking level carries most of that lead: from medium to max it gains 190 Elo. GPT-6 Astra (medium) sits 44 Elo above GPT-6.1 Terra (low) with overlapping ranges, though that alone does not test their difference, and it costs $0.262 against $0.027, almost ten times as much. Terra's five settings sit within 25 Elo of each other, and I would run low for a draft in 0.5 minutes. I'd never pick Astra at medium over Terra at low. Astra at max is the pick for a script I film when the bill doesn't bother me, and Terra at low covers every draft before that.

Disclosure: both models come from the same lab as one of the four judges, GPT-6.1 Sol. The other judges sit outside that lab, so neither is scored by its own lab alone (how the panel works). The judge analysis measures how much each judge favors its own lab.

How to Read the Writing Score, Writing Elo and 95% Ranges

Writing Score and Writing Elo. The Writing Score (0 to 100) is the weighted average of the nine metric scores: seven from the judges, Length Adherence from code and the Slop Score half from each. The Writing Elo is a rating from pairwise comparisons: on each script, each configuration's average across its drafts is compared with every other configuration's, and gaps within the draft-to-draft variation count as draws. Elo rewards winning often, so the two can put configurations in a different order.

Elo ranges. Each 95% range shows how far a configuration's Elo could move if the drafts had come out slightly differently. It comes from resampling every configuration's recorded draft scores on each reference script and ranking again. Comparing two separate ranges does not test the Elo gap between them: ranges far apart are strong evidence for the order, and overlapping ranges do not mean a tie. The reference scripts stay fixed, so the ranges say nothing about new scripts. The methodology page has the full description.

All Thinking Levels of Both Models

Every ranked configuration of GPT-6 Astra and GPT-6.1 Terra, scored on the same 10 scripts by the same four judges.

How to Read the Chart
  • Each row is one configuration: the model at one thinking level. The dot is its Writing Elo, a rating from pairwise comparisons of the scores on each script, and the bar is its 95% range: how far that Elo could move if the drafts had come out slightly differently.
  • Each bar describes one configuration. Overlap alone does not establish a tie or decide their order. Comparing these ranges does not directly test the difference between a pair.
  • The table under the chart lists the same configurations in the same order and adds the Writing Score (the 0 to 100 consensus of the judges and code), cost, time and configuration rank (the place among all configurations on the board).
GPT-6 AstraGPT-6.1 Terra
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptConfiguration Rank
GPT-6 Astra (max)21542110 to 218782.3$1.159.2 min#22
GPT-6 Astra (medium)19641933 to 199980.7$0.2621.5 min#37
GPT-6.1 Terra (max)19231884 to 195980.3$0.0791.8 min#43
GPT-6.1 Terra (high)19221881 to 195880.3$0.0270.5 min#44
GPT-6.1 Terra (low)19201879 to 196180.2$0.0270.5 min#46
GPT-6.1 Terra (xhigh)19061869 to 194480.1$0.0280.5 min#48
GPT-6.1 Terra (medium)18981852 to 194279.9$0.0270.5 min#49

Cost is one script at the API list price of the route used, uncached and without judging. Time is the average for one accepted script, retries included.

Computed Findings Across Thinking Levels

Each finding is computed from the configurations above. The 95% ranges describe individual configurations; overlap alone establishes neither a tie nor an order for a pair.

Writing Elo at Each Shared Level Name

LevelGPT-6 AstraGPT-6.1 TerraGap95% Ranges
medium19641898+66Overlap
max21541923+231Separate

Gap is GPT-6 Astra minus GPT-6.1 Terra at the same level name, using each model's highest-rated configuration at that level.

Two Chosen Configurations Compared

Pick one configuration of each model to compare their metric scores, consistency across drafts and per-script scores. Each menu starts on the model's best configuration.

Scores by Metric

GPT-6 Astra (max)GPT-6.1 Terra (max)Solid bar: higher score in that row

GPT-6 Astra (max) scores higher on all nine metrics. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put GPT-6 Astra (max) ahead, with a 3.8-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
77.8
74.0
Writing Craft & Clarity13% weight
78.4
78.3
Substance, Accuracy & Value15% weight
87.5
85.8
Continuity & Emotion14% weight
79.9
77.5
YouTube Best Practices12% weight
76.6
76.3
Hook Strength10% weight
82.1
80.6
Length Adherence8% weight
98.3
94.2
Slop Score5% weight
88.6
88.1
Visual Cue Quality4% weight
83.4
80.2

Consistency Across Drafts

GPT-6 Astra (max)GPT-6.1 Terra (max)
Score spread across drafts (±)1.871.68
Lowest script score80.6 Script 177.9 Script 10
Highest script score85.8 Script 983.2 Script 9
Range across scripts5.25.3

Spread is how much the Writing Score moves between a configuration's drafts, and lower is steadier. Green marks the better number in each row.

Scores by Script

Writing Score on each reference script. Gap is GPT-6 Astra (max) minus GPT-6.1 Terra (max), and the higher score is in bold.

ScriptGPT-6 Astra (max)GPT-6.1 Terra (max)Gap
Script 1 opinion / warning explainer80.680.2+0.4
Script 2 news-analysis / skeptical explainer82.080.7+1.3
Script 3 personal roadmap / opinion84.380.4+3.9
Script 4 short explainer82.779.6+3.1
Script 5 news-analysis / opinion explainer81.380.1+1.2
Script 6 founder announcement / personal origin story83.682.2+1.4
Script 7 personal technical walkthrough / agentic workflow case study81.679.9+1.7
Script 8 product release announcement / personal observation80.679.1+1.5
Script 9 career guide / hiring analysis85.883.2+2.6
Script 10 engineering process walkthrough / presentation adaptation80.777.9+2.8

Compare With Another Model

Pick a second model. A pair with its own written match-up opens that page, and any other pair opens in the comparison tool.

Nearby Match-Ups by Best Writing Elo

Every configuration wrote five drafts for each of the same 10 briefs, from the same prompt. Generation was closed-book, with the prompt as the only source and no web search or other tools. Each judge scores every draft once: Claude Opus 5.5 at medium effort through the Claude Code subscription, GPT-6.1 Sol at medium reasoning through the Codex CLI, GLM 5.3 Flash through OpenRouter, and Jev 1.13, a typed judge from TypeSafe that answers each metric as a multiple-choice question. The channel's finished script is their reference for the voice, and it gets no score on the board itself.

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