# Confidence vs Split (Harness FME): head-to-head

Last updated: 2026-05-04
Canonical source: https://confidence.spotify.com/comparisons/confidence-vs-split
Owner: Spotify AB

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Confidence vs Split (Harness FME) compared: an experimentation-first managed platform versus feature management inside the Harness CI/CD suite.

Harness announced its acquisition of Split on May 29, 2024, and
the deal closed June 11, 2024. Split was rebranded as Harness
Feature Management & Experimentation (FME) and is no longer an
independent experimentation vendor; it is one product inside
Harness's broader CI/CD and AI-delivery platform. The choice
between Confidence and Split is now a choice between an
experimentation-first managed platform and a feature management
product inside a DevOps platform built around software-delivery
automation.

Both products run as managed services. Both implement frequentist
sequential testing, sample ratio mismatch detection, and guardrail
metrics. CUPED variance reduction, which uses pre-experiment data
to tighten confidence intervals, is shipped on Confidence and is
not in Harness FME's public documentation. The differences live
in vendor parent, methodology depth, and which platform the
product is embedded in.

***

## What is Confidence?

Confidence is an experimentation platform with integrated feature
flags and analysis, built at Spotify over 15 years and now
available externally. It runs analysis inside your warehouse
(BigQuery, Snowflake, Redshift, or Databricks) and never stores
your raw user-level data. Today, 300+ Spotify teams use Confidence
to run 10,000+ experiments per year across 750 million users in
186 markets. 42% of those experiments are rolled back after
guardrail metrics flag a regression. The platform is tuned for
high-recall regression detection, which is the right trade-off
when shipping a regression to 750M users is more expensive than
missing an improvement.

Confidence does not offer Bayesian inference, multi-armed bandits,
or switchback experiments. The defaults reflect 15 years of
running experiments at Spotify scale, and the product team has
declined features that increased complexity without improving the
quality of decisions teams made.

***

## What is Split?

Split was a feature flag and experimentation platform founded in
2015 in Redwood City by Adil Aijaz, Patricio Echagüe, and Trevor
Stuart. Split raised more than \$100 million across Series A
through C and built a customer base in product-led organizations
including Twilio, Salesforce, GoDaddy, Electronic Arts, and Rocket
Mortgage.

In May 2024, Harness announced its acquisition of Split (deal
closed June 11, 2024; terms undisclosed). The product was rebranded
as Harness Feature Management & Experimentation (FME) and is now
sold as one of several products inside the Harness platform,
alongside Continuous Delivery, Continuous Integration, Cloud Cost
Management, and AI-powered code agents. The standalone "experimentation-
first feature flag" wedge that Split historically positioned
against LaunchDarkly is no longer the company's primary go-to-market;
Harness FME competes on platform-bundle economics across the
broader software-delivery story.

Harness FME's stats engine implements frequentist hypothesis
testing, mSPRT (mixture sequential probability ratio test) for
sequential testing, fixed-horizon analysis, sample ratio mismatch
detection (chi-squared with a p<0.001 threshold), guardrail
metrics, and Multiple Comparison Correction (MCC). CUPED variance
reduction is not listed in Harness FME's public stats documentation
as of 2026.

Recent product additions since the acquisition include
Warehouse-Native Experimentation, AI-driven experiment summarization,
an MCP server for AI IDEs, rule-based segments, a Reallocate
Traffic API, and (announced March 2026) AI-delivery release
coordination as part of the broader Harness platform release.

***

## Confidence vs Split, head-to-head

The differences live in vendor parent, methodology specifics
beyond the shared sequential testing and SRM surface, and which
platform the product is embedded in.

Vendor parent is the largest difference. Confidence is built and
operated by the team that runs Spotify's experimentation platform;
the roadmap is set by that team. Harness FME's roadmap is set
inside Harness, whose primary business is CI/CD, release
coordination, and AI-driven software delivery. Experimentation is
one product line inside a platform whose other products (Continuous
Delivery, Continuous Integration, Cloud Cost Management, AI code
agents) compete for engineering investment. For buyers making a
five-year platform decision, the question is whether the
experimentation product is the company's reason to exist
or one of several.

CUPED variance reduction is shipped on Confidence; it is not
listed in Harness FME's public stats documentation. Confidence's
CUPED uses the Negi–Wooldridge full regression estimator.
Buyers who need CUPED at Spotify scale on a managed warehouse-
native platform are choosing between Confidence, Eppo, GrowthBook
Cloud, and Statsig today; Harness FME's documented stats cover
sequential testing and SRM, but the variance-reduction surface
specifically is not detailed in public docs.

Operating-history evidence is asymmetric in shape, similar to
the LaunchDarkly comparison. Split's published references include
Twilio, Salesforce, GoDaddy, Electronic Arts, and Rocket Mortgage,
with legacy claims of "tens of millions of client apps and 1T+
events per month." Confidence has 10,000+ experiments per year
sustained for over a decade at Spotify, with 300+ teams on the
same platform across 750M users in 186 markets. Both are real;
the shape of the claim is breadth (Split's customer references and
event volume) versus depth (Confidence's continuous experimentation
program).

Compliance posture differs. Both products carry SOC 2 Type II.
Harness FME inherits ISO 27001/27017/27018 from the Harness
platform; FedRAMP and HIPAA are not publicly verified for FME as
of 2026. Confidence does not currently offer FedRAMP Moderate.

OpenFeature integration: Confidence's iOS and Android OpenFeature
provider SDKs were donated to the CNCF, and Spotify holds a seat
on the OpenFeature governance committee. Split maintains official
OpenFeature providers across .NET, Java, JavaScript, and Go but
is not on OpenFeature governance.

| Feature                        | Confidence                                                                 | Split (Harness FME)                                                       |
| ------------------------------ | -------------------------------------------------------------------------- | ------------------------------------------------------------------------- |
| Vendor parent                  | Spotify                                                                    | Harness (acquired June 2024)                                              |
| Product context                | Experimentation-only company                                               | One product inside Harness CI/CD + AI-delivery platform                   |
| Feature flags                  | First-class, in-process eval, no network call                              | First-class, originally Split's primary product                           |
| A/B testing                    | Built-in, frequentist, defaults tuned for high-recall regression detection | Built-in, frequentist                                                     |
| CUPED variance reduction       | Negi–Wooldridge full regression                                            | Not listed in public docs                                                 |
| Sequential testing             | Group Sequential Tests, always-valid inference                             | mSPRT (mixture sequential probability ratio test)                         |
| Sample ratio mismatch          | Default                                                                    | Default (chi-squared, p<0.001 threshold)                                  |
| Guardrail metrics              | Default                                                                    | Default                                                                   |
| Multiple comparison correction | Standard adjustments                                                       | MCC documented                                                            |
| Warehouse-native               | Primary architecture; raw data never stored                                | Available (added post-acquisition)                                        |
| Compliance                     | SOC 2 Type II                                                              | SOC 2 Type II, ISO 27001/27017/27018; FedRAMP/HIPAA not publicly verified |
| OpenFeature                    | Provider SDKs donated to CNCF; Spotify on governance                       | Official providers (.NET, Java, JS, Go); not on governance                |
| Pricing                        | Free self-serve trial; usage-based                                         | Free Developer tier (≤10 seats); Growth + Enterprise sales-gated          |

***

## Integrations comparison

Harness FME inherits the Harness platform's broader DevOps
integration set: CI/CD pipelines, observability, cloud platforms,
and now AI-driven code agents and release coordination. The MCP
server for AI IDEs ties experimentation into the Harness AI-delivery
story. For teams that want experimentation alongside their build
pipelines, deployment automation, and release coordination under
one vendor, Harness FME is the integrated answer.

Confidence integrates at the warehouse layer (BigQuery, Snowflake,
Redshift, Databricks) and at the SDK layer (OpenFeature, with
provider SDKs donated to the CNCF). Confidence does not bundle
CI/CD or release-orchestration tooling and routes teams to
dedicated platforms for those concerns.

***

## Pricing comparison

Harness FME has a free Developer tier (capped at 10 seats), a
usage-based Growth tier, and a sales-gated Enterprise tier. Tier
names are public; Growth and Enterprise pricing are not published.
The Harness platform pricing for Continuous Delivery and other
products is also tier-gated, and FME contracts often bundle with
the broader platform.

Confidence pricing scales with use and is structured around the
warehouse-native architecture. Confidence does not bill per-event
for raw user data it never stores. A free self-serve trial is
available at confidence.spotify.com without going through
procurement.

For teams that want experimentation alongside CI/CD and release
coordination under one vendor, Harness's bundle is the natural
fit; for teams that want experimentation as a discipline of its
own, the bundle is friction.

***

Harness FME fits organizations that want experimentation embedded
in their software-delivery platform alongside CI/CD, release
coordination, and AI-driven code workflows, and that have already
chosen Harness for the broader stack. Confidence fits teams that
want experimentation as a single managed product, with opinionated
defaults built on 15 years of Spotify operating evidence and a
roadmap set by the team that built it. The cost of picking the
wrong vendor parent is paid over five years of running an
experimentation program inside a platform whose engineering
investment is going to other product lines.

***

*See also: [Top 7 alternatives to Split](/comparisons/alternatives-to-split) · [What is Split?](/comparisons/what-is-split)*
