Best AI for coding
Scored 93/100 on our coding tests — level on quality with 2 others (GPT-5.6 Terra, GPT-5.6 Sol) — the top spot goes on the tie-break: cleanest rule-compliance, then lowest measured cost; 2 more sit a single point behind.
GPT-5.6 Luna is the engine inside ChatGPT. Go to chatgpt.com ↗ — the free tier is fine to start. Paid plans start at £7/month (go plan, vendor’s own price). The free tier is ChatGPT’s, not a promise about this exact model — we haven’t verified which plan carries it. Not fussed about the last point or two? Any of the top 5 here will serve you well.
Coding assistants are wrappers around models, so we test the flagship model each editor ships with — named on every score. The suite covers writing new code, finding real bugs, and explaining unfamiliar code, judged on correctness first.
updated 16 Aug 2026 · tested by Robert Prime · re-ranks automatically when a new run lands
| # | Tool | Our score |
|---|---|---|
| 1 | GPT-5.6 Lunalatest | 93/100 |
| 2 | GPT-5.6 Terralatest | 93/100 |
| 3 | GPT-5.6 Sollatest | 93/100 |
| 4 | GLM 5.2 | 92/100 |
| 5 | GPT-5.3-Codex | 92/100 |
| 6 | GPT-5.5 | 91/100 |
| 7 | GitHub Copilot | 90/100 |
| 8 | Qwen3.7 Max | 90/100 |
| 9 | Claude Opus 4.8 | 89/100 |
| 10 | Kimi K3 | 89/100 |
| 11 | Grok 4.5 | 88/100 |
| 12 | Gemini 3.1 Pro Preview | 88/100 |
| 13 | DeepSeek V4 Flash | 86/100 |
| 14 | Gemini 3.5 Flash | 86/100 |
| 15 | Cursor | 85/100 |
| 16 | Claude Opus 4.6 | 84/100 |
| 17 | DeepSeek V4 Pro | 83/100 |
| 18 | Claude Sonnet 5 | 83/100 |
| 19 | Gemini 3.1 Flash Lite | 77/100 |
| 20 | Mistral Medium 3.5 | 71/100 |
Made by OpenAI — their newest model. You use it inside ChatGPT — nothing to install.
Strongest showing: “Typed debounce” — scored 10/10 by the panel. Weakest: “Explain and cost” at 9/10.
“The response provides a flawless TypeScript debounce implementation that preserves types, includes a cancel method, avoids 'any', and accurately explains the type loss in exactly one sentence.”— google/gemini-3.1-pro-preview, judging blind · full receipts ↓
18 tasks · 16 Aug 2026 · judges claude-sonnet-5, gemini-3.1-pro-preview, grok-4.5 · API $0.2 in / $1.2 out per 1M tokens · full tool page →
Same maker, same score — effectively the same choice as #1; the deep-dive above covers it. Full model page →
Same maker, same score — effectively the same choice as #1; the deep-dive above covers it. Full model page →
See it for yourself
One task from the suite, and what the leader, the middle of the table and the bottom actually wrote. This is the task they disagreed on most — scores ranged from 3 to 10 out of 10.
Write a debounce function in TypeScript that preserves the argument types of the wrapped function, returns a function with a .cancel() method, and does not use 'any'. Explain in one sentence why the naive generic signature loses type information.
```ts
type Debounced<F extends (...args: never[]) => unknown> =
((...args: Parameters<F>) => void) & {
cancel(): void;
};
function debounce<F extends (...args: never[]) => unknown>(
fn: F,
delay: number
): Debounced<F> {
let timer: ReturnType<typeof setTimeout> | undefined;
let pend…Judge: The response provides a flawless TypeScript debounce implementation that preserves types, includes a cancel method, avoids 'any', and accurately explains the type loss in exactly one sentence.
```typescript
function debounce<TArgs extends unknown[]>(
fn: (...args: TArgs) => void,
delay: number
): ((...args: TArgs) => void) & { cancel(): void } {
let timeoutId: ReturnType<typeof setTimeout> | undefined;
const debounced = (...args: TArgs) => {
if (timeoutId !== undefined) clear…Judge: The code is excellent and meets all requirements, but the response violates the negative constraint by using the word 'any' in the explanation text.
Here's a debounce function in TypeScript that meets your requirements:
```typescript
function debounce<T extends (...args: any[]) => any>(
func: T,
wait: number
): {
(...args: Parameters<T>): void;
cancel: () => void;
} {
let timeoutId: ReturnType<typeof setTimeout> | null = null;
cons…Judge: The response explicitly uses the forbidden word 'any' in the type constraint `T extends (...args: any[]) => any`, violating the negative constraint.
Trimmed to fit. Every full answer, every judge’s score: GPT-5.6 Luna, Grok 4.5, Mistral Medium 3.5
How this ranking is made
Every tool answers the identical published task suite. Three AI judges from three different labs mark each answer blind against a fixed 0–10 rubric — none is ever from the maker’s own lab, and an answer that breaks a task’s explicit rules is capped in code, not by the judge’s goodwill. The score is the average, out of 100.
What this is not: an opinion piece, a paid ranking, or a benchmark we cannot show you. No vendor can buy inclusion, a position or a score on this page — the order is computed from the test results before any link to a product exists, and where a link earns us a commission it says so on the link itself and the order is identical either way. Every score links its raw outputs and judge verdicts. The full protocol · How we make money · receipts: GPT-5.6 Luna, GPT-5.6 Terra, GPT-5.6 Sol, GLM 5.2, GPT-5.3-Codex, GPT-5.5, GitHub Copilot, Qwen3.7 Max, Claude Opus 4.8, Kimi K3, Grok 4.5, Gemini 3.1 Pro Preview, DeepSeek V4 Flash, Gemini 3.5 Flash, Cursor, Claude Opus 4.6, DeepSeek V4 Pro, Claude Sonnet 5, Gemini 3.1 Flash Lite, Mistral Medium 3.5
Questions people ask
What is the best AI for coding in 2026?
GPT-5.6 Luna leads our tested ranking with 93/100 on our coding tests (18 tasks), in a dead heat with GPT-5.6 Terra (93). Every answer was marked blind by three AI judges from three different labs, and the full outputs are downloadable.
How is this ranking made?
Each tool answers the identical published task suite; three judges from different labs score every answer 0–10 against a fixed rubric without knowing which produced it; answers that break a task's explicit rules are capped automatically. The score is the average, out of 100. No vendor pays for placement.
How often does this page update?
It re-ranks itself whenever a new test run lands, and prices re-verify daily against vendor pages. The current ranking was last computed on 16 Aug 2026.
Head-to-head in coding
Head-to-heads in coding
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