
Helicone AI
LangSmith
LangChain
Braintrust.dev
Portkey
PromptLayer
LastMile AI
Langfuse is an open-source LLM engineering platform that helps teams collaboratively debug, analyze, and iterate on their LLM applications.

OpenAI
Gemini.com
LLM Cost Calculator
Gemini 2.5 Flash
GPT3 Crush
OpenRouter
SharpAPI
Estimate LLM API costs before you build — GPT-4, Claude, Gemini

Which is more popular?
Based on our record, Langfuse seems to be more popular. It has been mentioned 33 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | langfuse.com | utilitylab.dev |
| Pricing | ||
| Company | Startup from the United States | 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


Langfuse is an open-source LLM engineering platform designed to empower developers by providing insights into user interactions with their LLM applications. We offer tools that help developers understand usage patterns, diagnose issues, and improve application performance based on real user data....
Free browser-based tool to estimate API costs for GPT-4, Claude, Gemini, and open-source models. Calculate prompt, completion, and monthly token expenses before writing code. No sign-up required. AI Cost Simulator helps developers and teams estimate LLM API pricing before they ship. Select from...
What each product offers, as listed by its team.


Possible disadvantages
Walkthroughs and reviews on video.
Langfuse in two minutes
No UtilityLab.dev videos yet. You could help us improve this page by suggesting one.
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Langfuse and UtilityLab.dev.
UtilityLab.dev's answer:
Most LLM cost calculators are either spreadsheets or require signing up for an API. AI Cost Simulator is a free, browser-based tool that works instantly — no account, no installation, no data upload. It supports the widest range of models (GPT-4o, Claude 3.5 Sonnet, Gemini 1.5 Pro, DeepSeek V4 Flash, and more) with both per-call and monthly volume estimates in one view.
UtilityLab.dev's answer:
Vanilla JavaScript, HTML, and CSS — no frameworks, no bundlers. All cost calculations happen client-side. The tool is deployed as a static site on Cloudflare Pages for global low-latency access.
UtilityLab.dev's answer:
It's the only zero-friction cost estimator. Competitors either lock features behind sign-up walls, only support one model family, or require you to dig through separate pricing pages. AI Cost Simulator gives you a side-by-side comparison of all major LLM providers in one page — and everything runs locally in your browser, so your pricing data never leaves your machine.
UtilityLab.dev's answer:
Developers, indie hackers, and technical founders who are evaluating LLM APIs for their next project. Also product managers and engineering leads doing cost analysis before committing to a model provider at scale.
UtilityLab.dev's answer:
When building AI-powered features, we realized every model provider publishes pricing differently — per-token, per-character, per-request — and there's no single place to compare them. Instead of bookmarking five pricing pages and building a spreadsheet, we built a dead-simple comparison tool. We open-sourced the approach and made it free so other developers don't have to waste time doing manual math.
UtilityLab.dev's answer:
Since it's a free browser tool with no sign-up, we don't track individual users. It's used by developers and teams evaluating LLM costs across startups, agencies, and enterprise engineering teams.
Share your experience with using Langfuse and UtilityLab.dev. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Ten free AI prompt tools in 2026 across four categories: prompt generators (SurePrompts, Anthropic Console, OpenAI Playground), libraries (AIPRM, PromptHero, FlowGPT, Awesome ChatGPT Prompts), open-source workflow...
We have no reviews of UtilityLab.dev yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


We have researched and experimented with several AI evaluation platforms, including Arize Phoenix, Microsoft Foundry, and Langfuse. After evaluating them against our requirements and roadmap, we shortlisted Microsoft Foundry and Langfuse... - Source: dev.to / 8 days ago
Langfuse is the other serious option in this category if you also want observability, evals and traces bundled with prompt management. Different scope, more setup, worth comparing honestly. - Source: dev.to / 29 days ago
Langfuse with Microsoft.Extensions.AI has an appealing story: update prompts without redeploying. A prompt fetches its config blob—model, tokens, temperature—which the code passes straight to the LLM. - Source: dev.to / about 1 month ago
Tracking UtilityLab.dev since Jul 2026.
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