---
type: source
title: "Let's Settle the o3-mini Vs. R1 Debate for Coding ONCE and for ALL"
description: "By building the same apps in bolt.diy with both OpenAI's o3-mini and DeepSeek R1, Cole finds no single winner: o3-mini is faster and more literally correct while R1 produces nicer UIs and reasons better about unstated needs, so the two are best used together."
youtube_id: xfFyAumTjT0
url: https://www.youtube.com/watch?v=xfFyAumTjT0
slug: lets-settle-the-o3-mini-vs-r1-debate-for-coding-once-and-for-all
published: 2025-02-05
duration: "0:19:14"
recency_rank: 119
raw: "../raw/lets-settle-the-o3-mini-vs-r1-debate-for-coding-once-and-for-all.md"
tags: [model-selection, reasoning-models, o3-mini, deepseek-r1]
created: 2026-07-21
updated: 2026-07-21
---

# Let's Settle the o3-mini Vs. R1 Debate for Coding ONCE and for ALL

Cole runs a hands-on, head-to-head coding bake-off between OpenAI's o3-mini and the open-source DeepSeek R1, using the open-source bolt.diy coding assistant to build identical apps with each model. He frames the comparison carefully: the two are architecturally different (o3-mini is a dense Transformer, R1 is a mixture-of-experts trained with RLHF), o3-mini tends to be stronger on directed agent-style tasks while R1 excels at logical, free-thinking work, and R1 is open source and far cheaper. He tests across escalating difficulty: a simple todo app, a detailed Supabase-backed agent chat frontend, and a single-sentence "build a chess site" prompt.

The pattern that emerges is consistent. o3-mini is noticeably faster (10s vs 20-30s on simple apps, and the gap widens on complex ones) and tends to implement functionality more correctly, for example handling illegal chess moves. R1 is slower but frequently one-shots working apps, produces better-looking UIs, and infers features Cole never asked for, like a live task-completion counter and empty-state copy. On the complex chat frontend, o3-mini took several error-fix cycles to compile while R1 compiled on the first try, yet R1 had a few functional glitches (conversations not loading) that o3-mini handled.

Cole's takeaway is that there is no clean winner. Use o3-mini for speed and reliable functionality, R1 for UI polish and intent understanding, and ideally combine them. He also plugs bolt.diy itself as the real winner, since it lets you swap in any LLM as your coding harness.

## Concepts covered

- [Model Selection](../concepts/model-selection.md)
- [Reasoning Models](../concepts/reasoning-models.md)
- [AI Coding Harness](../concepts/ai-coding-harness.md)
- [Vibe Coding](../concepts/vibe-coding.md)
- [Rapid Prototyping](../concepts/rapid-prototyping.md)
- [Clarifying Questions](../concepts/clarifying-questions.md)
- [The Ralph Loop](../concepts/the-ralph-loop.md)

## Entities

- [DeepSeek R1](../entities/tools/deepseek-r1.md)
- [bolt.diy](../entities/tools/bolt-diy.md)
- [OpenAI](../entities/organizations/openai.md)
- [OpenRouter](../entities/tools/openrouter.md)
- [Supabase](../entities/tools/supabase.md)
- [Cole Medin](../entities/people/cole-medin.md)

## Key moments

- **[0:00:00]** Framing: after DeepSeek R1's release, OpenAI fires back with o3-mini; both are strong reasoning LLMs and the video will settle which is better for coding
- **[0:02:23]** Architecture contrast from a Hugging Face writeup: o3-mini is a dense Transformer, R1 is mixture-of-experts + RLHF
- **[0:03:30]** Setup: testing in bolt.diy, o3-mini via OpenAI API, R1 via OpenRouter (Nitro) due to DeepSeek API outages
- **[0:05:35]** Test 1 (simple todo app): o3-mini builds in ~10s but doesn't run the site; R1 slower but one-shots and infers extra features
- **[0:10:34]** Test 2 (Supabase agent chat frontend, detailed prompt): o3-mini needs several error-fix cycles; R1 compiles first try but has glitches
- **[0:15:13]** Test 3 (single-sentence chess site): o3-mini handles illegal moves better; R1 has the far nicer board; neither enforces rules well
- **[0:17:44]** Verdict: R1 wins UI and intent-understanding, o3-mini wins speed and functional correctness; use them together

## Transcript

[Raw transcript](../raw/lets-settle-the-o3-mini-vs-r1-debate-for-coding-once-and-for-all.md)
