Cheapest platform as trace volume grows
Seats, payload size and score volume held at your current inputs β only monthly trace volume changes per row. Watch Galileo's flat fee win at low-mid volume, then hit "Enterprise" while LangSmith and Braintrust keep scaling self-serve.
| Traces / mo | LangSmith | Braintrust | Galileo | Cheapest |
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Why per-seat, per-GB and flat-fee billing shapes matter
LLM eval and observability platforms don't compete on a single price β each meters a completely different dimension of your workload. LangSmith bills cost = seats Γ $39 + max(0, traces - included) Γ· 1000 Γ $2.50 on the Plus plan (Developer is free but capped at exactly 1 seat with 5,000 base traces included; Plus includes 10,000 base traces per org). Braintrust bills cost = max(0, dataGB - includedGB) Γ gbRate + max(0, scores - includedScores) Γ· 1000 Γ scoreRate where dataGB = traces Γ avgPayloadKB Γ· 1,048,576 β Starter is free with 1GB/10,000 scores included ($4/GB and $2.50/1k score overage), Pro is a flat $249/month with 5GB/50,000 scores included ($3/GB and $1.50/1k score overage) β and critically, both Braintrust tiers include unlimited seats, so team size never affects the bill. Galileo is the simplest: Free covers 5,000 traces/month at $0, Pro is a flat $100/month (billed yearly) covering roughly 50,000 traces/month, and beyond that there's no published self-serve rate β you need an Enterprise quote.
The calculator automatically picks whichever published tier is cheapest for each vendor at your inputs (e.g. it will keep you on Braintrust's free Starter tier paying only overage rather than jumping to the $249 Pro plan, if that's actually cheaper). That means the "winner" flips hard depending on your shape: a small team with light eval volume usually wins on Braintrust's free tier since it has no seat cost at all; a larger team with predictable, moderate trace volume often does best on LangSmith's fixed per-seat Plus plan; and heavy trace volume forces Galileo out of self-serve pricing entirely. Payload size per trace matters too β the same trace count costs Braintrust very differently depending on how much data each trace carries, while LangSmith and Galileo only count traces, not their size.
How this calculator works
The LangSmith vs Braintrust vs Galileo Cost Calculator compares three LLM eval/observability pricing shapes β LangSmith (per human seat + per base trace over a quota), Braintrust (per GB of data processed + per evaluation score over a quota, unlimited seats) and Galileo (flat monthly fee up to a trace cap, then Enterprise-only) β at your team size, monthly trace volume, average trace payload size and monthly evaluation score volume. For each vendor the calculator checks every published self-serve tier and returns whichever is cheapest for your inputs: LangSmith checks Developer (1 seat max, free, 5,000 base traces included, then $2.50/1k traces) against Plus (seats Γ $39 plus 10,000 base traces included org-wide, then $2.50/1k traces over that); Braintrust converts your trace count and payload size into processed GB (traces Γ payloadKB Γ· 1,048,576) and checks Starter (free, 1GB + 10,000 scores included, $4/GB and $2.50/1k score overage) against Pro (flat $249/month, 5GB + 50,000 scores included, $3/GB and $1.50/1k score overage); Galileo checks Free (5,000 traces included, $0) against Pro (flat $100/month for up to roughly 50,000 traces/month) and flags anything above that as requiring an Enterprise quote. The second table sweeps trace volume from 5,000 to 1,000,000/month at your current seats, payload size and score inputs so you can see exactly where each platform's cheapest tier changes and where Galileo drops out of self-serve pricing.
These are representative pricing shapes based on each vendor's published self-serve rates as of August 2026 β Braintrust's Starter and Pro tiers (data, score and retention rates) from braintrust.dev/pricing; Galileo's Free and Pro tiers from galileo.ai/pricing; LangSmith's Developer and Plus seat prices and included base-trace quotas from langchain.com/pricing-langsmith. LangSmith's exact overage rate is billed in LangChain Compute Units (LCU) and Storage Units (LSU) rather than a flat per-trace price, so the $2.50/1,000-base-trace figure used here is a widely reported approximation of that unit cost, not LangSmith's literal billing line item β confirm your own LCU/LSU consumption on LangSmith's usage dashboard before budgeting. Enterprise tiers for all three vendors are negotiated separately and aren't modeled here. Always confirm current pricing directly with each vendor before budgeting.
Frequently asked questions
Why is Braintrust cheaper than LangSmith for small teams but not always for large ones?
Braintrust's free Starter tier has no seat fee at all β it bills processed data (GB) and scores, with unlimited users included, so a small team doing light evals often stays entirely inside the free 1GB / 10,000-score allowance or pays only a small overage. LangSmith's Developer plan is free too, but it caps out at exactly 1 seat β add a second teammate and you're on the Plus plan at $39/seat/month whether you use it or not. That fixed per-seat cost is what makes LangSmith look expensive for small teams. But as trace volume and payload size grow, Braintrust's per-GB processed-data charge scales with how much data each trace carries, while LangSmith only charges for trace count β so a large team running many small, lightweight traces can end up cheaper on LangSmith's per-seat-plus-per-trace model than on Braintrust's per-GB model, especially once Braintrust's flat $249/month Pro plan kicks in.
What happens when I exceed Galileo's Pro trace limit?
Galileo's Free tier covers 5,000 traces/month and its Pro tier is a flat $100/month (billed yearly) that covers roughly 50,000 traces/month. Unlike LangSmith ($2.50 per 1,000 base traces over the included quota) and Braintrust ($3-4 per GB and $1.50-2.50 per 1,000 scores over quota), Galileo does not publish a self-serve per-trace overage rate beyond the Pro tier β once you exceed roughly 50,000 traces/month you have to move to Enterprise and contact sales for custom pricing. That makes Galileo predictable and cheap at low-to-moderate volume but the least self-serve-friendly of the three once you scale past its published tiers.
Does Braintrust really let me add unlimited team members for free?
Yes β both Braintrust's Starter (free) and Pro ($249/month) plans explicitly include unlimited users, projects and datasets at no extra charge. Braintrust doesn't meter seats at all; it meters processed data volume (GB) and evaluation scores instead. That's the opposite of LangSmith, which is fundamentally seat-priced ($0 for 1 seat, $39/seat/month beyond that) with trace volume as a secondary, usage-based charge on top. If your team is large but your eval/trace volume is light, Braintrust's model can be dramatically cheaper; if your team is small but you process a lot of data per trace, the per-GB charge can flip that advantage.
Which LLM eval and observability platform is cheapest overall?
There's no universal winner β it depends on team size, trace volume, average payload size per trace, and how many evaluation scores you run. As a rule of thumb: small teams with light eval volume usually land cheapest on Braintrust's free Starter tier (no seat cost, generous free data/score allowance). Larger teams with moderate, predictable trace volume often do best on LangSmith's Plus plan, since its per-seat cost is fixed and its per-trace overage rate is transparent at any volume. Very high-volume users (above roughly 50,000 traces/month) will find Galileo requires an Enterprise conversation, while LangSmith and Braintrust both let you keep scaling self-serve using their published overage rates. Run your own seats, trace volume, payload size and score volume through the calculator above rather than trusting list prices alone.