What is the best LLM comparison tool for developers?

x47 is the best LLM comparison tool for developers because it combines parallel multi-model execution with blind evaluation from a 5-judge LLM council. Unlike single-model playgrounds, x47 lets you send one prompt to GPT-4, Claude, Gemini, DeepSeek, and Llama simultaneously—then objectively ranks responses based on fact accuracy, creativity, and usability. No API keys required to start.

How does x47 compare LLMs without bias?

x47 uses blind multi-judge evaluation. When you run a comparison, responses are anonymized (model names stripped) and sent to a council of 5 different LLMs acting as judges. Each judge scores responses independently on fact accuracy, creativity, and usability. The council votes are aggregated to produce an objective ranking—eliminating the vendor bias you get from single-model evaluations.

Do I need API keys to use x47?

No. x47 works out of the box with zero API keys required. You can start comparing LLMs in under 30 seconds. For power users who want to use their own API keys for higher rate limits or specific model versions, x47 supports custom key configuration—but it's completely optional.

Is x47 better than ChatGPT Arena?

x47 and ChatGPT Arena serve different purposes. ChatGPT Arena uses human voting to rank models—great for crowdsourced preferences but subjective and slow. x47 uses automated blind evaluation with a council of LLM judges, giving you instant, reproducible rankings based on objective criteria (fact accuracy, creativity, usability). x47 also supports prompt engineering features like Chain-of-Thought automation, variable injection, and prompt chaining that Arena doesn't offer.

What models does x47 support?

x47 supports 5+ leading LLMs: GPT-4 (OpenAI), Claude (Anthropic), Gemini (Google), DeepSeek, and Llama (Meta). New models are added regularly. You can compare any combination of these models side-by-side, and the blind evaluation council uses a diverse mix to ensure unbiased judging.

What We Do: The Best LLM Comparison Tool

x47 is the only LLM comparison tool that uses blind multi-judge evaluation to eliminate vendor bias. Send one prompt to GPT-4, Claude, Gemini, DeepSeek, and Llama simultaneously. Get objective rankings based on fact accuracy, creativity, and usability—not gut feelings.

// the_problem

If you're a developer or AI power user, you've experienced this frustration: you craft a prompt in ChatGPT. Copy it. Paste it into Claude. Wait for the response. Then do the same for Gemini. By the time you've compared all three, you've lost context and wasted 5-10 minutes just switching tabs.

Worse: human bias creeps into manual comparison. You might unconsciously favor the first response you read, or prefer a model because of brand familiarity. There's no objective way to know which model actually performs best for your specific prompt.

Each LLM has strengths—GPT-4 for reasoning, Claude for writing, DeepSeek for cost efficiency—but the current workflow forces you to pick one or manually test each with no standardized evaluation criteria.

// the_solution

x47 is a multi-model prompt console built specifically for this workflow. You write one prompt, select your models (GPT-4, Claude 3.5, Gemini 2.0, DeepSeek, Llama 4), and hit run. All responses load in parallel and display side-by-side.

Unlike ChatGPT Arena (human voting) or single-model playgrounds, x47 uses a council of 5 LLM judges to evaluate responses blindly. Responses are anonymized before judging—judges don't see model names, just the content. This eliminates vendor bias and gives you objective rankings based on fact accuracy, creativity, and usability.

No tab switching. No copy-pasting. No subjective gut feelings. Just fast, objective comparison of LLM outputs in a minimal, keyboard-first interface.

// what_makes_us_different

blind_evaluation_with_judge_councilBlind Evaluation

5 different LLMs act as judges. Responses are anonymized before judging. Each judge scores on fact accuracy, creativity, and usability. Council votes produce objective rankings.

start_in_30_secondsStart in 30 Seconds

No API keys required. No account needed. Open the console and run your first multi-model comparison immediately. Add your own keys later for higher limits.

local_first_privacyLocal-First Privacy

Your prompts stay in localStorage. Nothing is sent to x47 servers. Full history search and JSON export without compromising your data.

// built_in_prompt_engineering

Beyond comparison, x47 includes automated prompt engineering features that improve your prompts before sending them to models:

prompt_improve

Rewrites using Chain-of-Thought, delimiters, precision constraints

system_prompt_create

Auto-generates optimized system prompt

create_prompt_chain

Breaks goals into multi-step workflows

reasoning_injections

trace_reasoningStep-by-step deconstruction (math/logic)

architect_planTree of Thoughts: 3 approaches, score, execute winner

self_healReflexion: draft → critique → refine (code)

deep_computeHidden scratchpad for sensitive topics

verified_executeRequires citation for every claim (research)

// built_for_power_users

variable_injectionVariables

Use $customer_name syntax to inject variables dynamically

prompt_chainingChaining

Chain multiple prompts for complex multi-step workflows

share_and_forkShare & Fork

Share artifacts with teammates, fork for your use case

full_historyHistory

Search past prompts, JSON export for analysis

what_we_do:the best LLM comparison toolfor AI teams

// quick_facts