Braintrust vs PromptLayer (2026): Pricing, Features & Which to Choose

Who comes out ahead

Based only on the facts in our directory. The right pick still depends on the job you need done.

Lower starting price
Not comparable
Not comparable: PromptLayer does not list a price
Free plan
Tie
Both have one
Higher rating
Braintrust
4.2 against 3.9
Same job?
Yes
Both are AI Infrastructure & Agent Tooling tools

Side by side

Compared on	Braintrust	PromptLayer
Our rating	4.2Better	3.9
Starts at	$249/mo	Free
Free plan	Yes	Yes
Category	AI Infrastructure & Agent Tooling	AI Infrastructure & Agent Tooling
Plans	From $249/mo	Free
Key features	Evaluation-first platform, not just logging and tracing after the fact Lets teams test and score AI product behavior before shipping Tracing priced per GB for production observability $80M Series B led by ICONIQ Capital in February 2026 Backed by Andreessen Horowitz, Greylock, and Elad Gil	Prompt registry with versioning Evaluation harness for regression testing prompts Request observability and tracing Visual editor for non-engineers Collaboration without codebase access
Pros	Evaluation-first approach catches failures a pure logging tool would only surface after the fact Strong-name investor backing signals real staying power in a crowded observability market Simple two-tier pricing is easier to reason about than usage-based competitors with many tiers	Lets domain experts improve prompts without a deploy cycle Evaluations prevent well-meaning edits silently breaking cases Covers management, testing and observability rather than one slice
Cons	Jump from free straight to $249/month with no mid-tier option limits gradual scaling Per-GB tracing costs require monitoring at high production volume Newer entrant competing against more established observability platforms like Arize and LangSmith	Overhead is hard to justify for a single-developer project Another dependency in the request path to monitor Meaningful evaluation still requires you to build the test cases
Company	Braintrust, founded 2023	PromptLayer

Prices come from each vendor's pricing page, last checked 20260901. Check the vendor before you buy.

FAQ

Questions people ask

Is Braintrust better than PromptLayer?

In our reviews Braintrust scores 4.2 and PromptLayer scores 3.9. The better pick depends on the job. Braintrust: Raised an ICONIQ-led $80M Series B building the evaluation layer teams use to ship AI products with confidence. PromptLayer: Prompt registry, evaluation harness and observability in one place - so domain experts can change prompts without touching your codebase.

Which is cheaper, Braintrust or PromptLayer?

Braintrust: from $249/mo. PromptLayer: free.

Do Braintrust and PromptLayer have free plans?

Yes, both have a free plan.

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