Sierra vs Superhuman

Sierra — Application · Private · $15.8B valuation · 4 of 4 figures sourced  |  Superhuman — Application · Private · 1 of 1 figure sourced

Relationship

Assembled from the recorded fields for this pair, not hand-checked. The comparison below is read from each company’s own profile.

Aligned comparison

FieldSierraSuperhuman
Size$15.8B valuationnot disclosed
Employees549—
Founded20232009 14 yrs earlier
StatusPrivatePrivate match
CategoryApplicationApplication match
Stack layerAI agent, Application, Developer toolApplication, Platform
HeadquartersSan Francisco, USASan Francisco, USA match

Capability overlap

Shared · 3

Agent orchestrationText generationWorkflow automation

Not verified for Superhuman · 4

Customer supportData analysisEvaluation and observabilityVoice agent

Recorded for Sierra. Superhuman’s product records say nothing either way — a missing record is not a missing capability.

Not verified for Sierra · 2

Email assistanceSummarization

Recorded for Superhuman. Sierra’s product records say nothing either way — a missing record is not a missing capability.

Products, side by side

Algorithmic pairing — assembled from recorded fields, not hand-checked

Sierra

Application

Agent StudioApplication

Empower customer experience teams to build and manage agents—without writing a line of code. Set up customer journeys, configure knowledge, and define brand guidelines effortlessly.

ChannelsApplication

Create consistent experiences across voice, chat, email, and more in 58 languages, available 24/7/365.

ExplorerApplication

Ask any question in natural language, and Explorer will use analytics and sample customer conversations to provide answers and actionable recommendations.

GhostwriterApplication

Build or modify your agent simply by describing how you want your agent to behave. Prompt workflows, systems integrations, guardrails, tone, and style.

HorizonApplication

Long-horizon agents that get more intelligent with every interaction.

InsightsApplication

Measure what matters, test what works, and understand every agent decision with analytics, experimentation, and observability built for continuous improvement.

Superhuman

Application

GrammarlyApplication

The writing assistant that gave the company its old name: spelling, grammar and tone correction across a million apps and websites, with generative rewrites, plagiarism and AI-text detection on the paid tier.

Superhuman DocsApplication

A collaborative-docs surface where a team's data and AI meet, the renamed successor to the acquired Coda.

Superhuman GoApplication

An AI assistant that works across the applications a person already uses, rather than living in its own chat window.

Superhuman MailApplication

An AI-assisted email client, the product the company was originally named for, now sold as one app inside the Superhuman Platform.

No counterpart

Sierra sells these in a stack layer with no product recorded for Superhuman yet — nothing on the other side to compare them against.

AI agent

SierraAI agent

Platform for building and running customer-facing agents that handle support conversations over chat and voice.

Developer tool

Context EngineDeveloper tool

Supplies persistent customer context and behavioral signals to Sierra's conversational agents.

Superhuman sells these in a stack layer with no product recorded for Sierra yet — nothing on the other side to compare them against.

Platform

Superhuman PlatformPlatform

The umbrella under which Superhuman now sells Mail, Docs and Go as one subscription, plus a marketplace of third-party agents and connectors.