Best Authentication Providers in 2026

The feature grids overlap, yet a retained-user plan, a monthly-active plan, and a per-connection plan can all advertise MFA and still fail a different month. Pick the meter before the logo. A launch full of one-time signups looks cheap on a retained-user bill and expensive on a monthly-active bill. One customer identity provider can outweigh a large block of ordinary logins, which is why the connection fee belongs beside the user rate.

Toolradar data: the identity and access directory we run listed 103 tools on October 16, 2026. Keycloak is named as an alternative on 59 of those records, and Auth0 on 56, on the identity and access ranking. That shelf is wider than app login, because password managers and workforce suites sit in the same category. This page keeps the customer-login products a product team would actually ship.

Methodology: plan cards, feature rows, and user steps were checked on October 17, 2026, on each vendor's pricing page, plus the product pages for Clerk, Auth0, WorkOS, Cognito, Firebase Authentication, Better Auth, and Keycloak. No production tenant was opened. A total that multiplies a published rate by a user count is our arithmetic, and the sentence says so. The longer Clerk review and Auth0 review stay on those two products.

An authentication provider is the service, or the server you run, that creates the user, checks the password or the SSO assertion, and hands your app a session. The purchase is the user record and the login screen, not a database and not a workforce directory, so a Postgres search or an employee suite is a different buy.

Hosted products keep that record for you, which is why Clerk, WorkOS, Auth0, Stytch, Cognito, and Firebase Authentication suit a team that wants a vendor on the line when sign-in fails. Supabase Auth joins them only when the project is already Supabase. FusionAuth Community, Better Auth, and Keycloak put the record on infrastructure you patch, which suits a team that already runs that box.

Leaving a hosted pool means exporting the user record, while leaving Keycloak means taking the database you already back up. A consumer app bills people who signed up for your product. A B2B app also has to satisfy the customer's IT team, because they will ask for SAML or OIDC, and sometimes SCIM, before they sign.

Auth0 publishes those buyers as two price lists, so the cheap consumer card can drop the enterprise connection the free plan included. WorkOS and Stytch publish a connection fee, which is the bill when the customer's identity provider is the requirement. Clerk includes one enterprise connection on Pro and prices the next one, so a second customer IdP is another line.

Clerk ships sign-in components for Next.js, React, Expo, and Astro, so a React team can theme a finished form. FirebaseUI, AuthKit, and Cognito's managed login page are vendor screens you configure. Better Auth ships functions you call from your own routes, which is the path when every pixel must be yours. Keycloak ships a server login plus single sign-out across the apps that trust it, so several apps can share one session.

The bill moves when a feature leaves the free plan, which is often before the user count does. MFA, a fourth teammate, or one customer IdP is enough to end a free prototype. Auth0 Free includes one enterprise connection and does not include Pro MFA, so a second factor can push you onto a paid grid that drops that connection. Clerk Hobby includes neither MFA nor that connection, and it stops at three dashboard seats, the same cap as Pro, so a fourth person who needs a second factor is off both plans.

A quiet staging app fails for a different reason than a missing feature. Supabase pauses a free project after a week without traffic, and only two free projects can be active, so a demo you leave untouched can be asleep on Monday. WorkOS does not bill staging environments, so a sales copy stays off the invoice. Cognito's free tier for direct sign-in does not expire after 12 months, so an AWS prototype is not on a countdown.

Self-hosting trades the user meter for a pager. Keycloak, FusionAuth's free Community download, and the Better Auth framework have no end-user price, so the cost is the machine, the upgrade, and the person who answers when login is down. Pair that path with self-hosting tools and a host you already patch. Hosted login next to a hosted database is the other path, covered in the backend-as-a-service roundup and the Supabase review.

Vendor changes to these meters are the sort of note that lands in the Devshot brief. If the frontend host is still open, the Vercel review is the page beside this one, because several of these SDKs assume that deploy target.

Prices below were checked on October 17, 2026. The scenario is one production app, 10,000 users, MFA on, one enterprise SSO connection, and three people who can open the dashboard. Where a vendor publishes that step, the cell is quoted, and where the vendor publishes a rate, the extension is our arithmetic.

Clerk Pro covers this job on the monthly plan if three people can open the dashboard. Users sit inside the retained-user allowance, with MFA and one enterprise connection included, so those requirements do not force a higher plan. A fourth person has no seat on Pro, so the plan becomes Business, a seat change rather than a user-count change. The Clerk pricing page is the source for those rules.

WorkOS prices the connection and not the users, so it wins when a customer identity provider is the requirement and headcount is still inside the free production allowance. One SSO connection is the first-band fee, MFA sits inside AuthKit, and Directory Sync is a second connection on the same schedule if the customer also wants SCIM. A consumer app with no customer IdP never starts that fee. The rates are on the WorkOS pricing page.

Auth0 cannot do this job on the cheap B2C card. Free includes the enterprise connection and excludes Pro MFA, so MFA forces a paid plan, and the B2C table marks enterprise connections unavailable. B2C Essentials at this headcount is $700/mo and still omits the connection, so you can pay and still fail. B2B Essentials at 10,000 users is the $2,100/mo cell, with three connections and Pro MFA included. Skip that cell if the customer's login is not worth it. Those cells are on the Auth0 pricing page. Above them, Enterprise is contact sales and publishes no rate.

Supabase Pro's allowance and basic MFA cover email or social sign-in here, so a second auth vendor would duplicate a database you already run. SAML is a different line: 50 MAU included, then a per-MAU rate. Extending that rate across the other 9,950 users is $149.25, before the organization fee, and Supabase does not publish that total, while phone MFA is a separate project fee. Read both on the Supabase pricing page. The database side of the same invoice is the Supabase vs Firebase note.

Cognito Essentials keeps direct or social users at this size inside the free tier, so this password pool has no user charge. Price it before a specialist when the account is already AWS. Federated SAML or OIDC users sit outside that free tier, and AWS prices them after 50 MAU at the Essentials per-user rate, so a customer IdP starts the bill early. The Lite example for 950,000 direct MAU is $4,405, built from the two published rates on 90,000 MAU and then on 850,000, which describes a large consumer pool rather than this scenario. Machine tokens in the US East (N. Virginia) example are $0.00225 each. The Cognito pricing page is the source, and the product page is Amazon Cognito.

Firebase Authentication on the base product does not use the Identity Platform table, so leave the upgrade off when email and social login are enough. Turning it on drops Spark to 3,000 daily active users for email and social, and Blaze uses monthly-active bands that step down as the pool grows. SAML is free for 50 MAU per project, then a per-MAU rate, a different meter from email. US texts are on the Identity Platform pricing page. Larger totals for Clerk, Auth0, Supabase, and Firebase belong on authentication pricing compared, not in this ranking.

Stytch pay as you go includes this scenario at a free base, so it beats a per-connection card when more than one customer brings an identity provider. It does not publish a per-member price past the included allowance. Fingerprints and the brand fee are optional lines on the Stytch pricing page.

At this headcount, FusionAuth lists Starter at the same annual rate as the smaller step, so that card does not climb, and Essentials at $1,500/mo billed annually is the step that climbs. Self-host Community stays free, hosted Community stays at $37/mo, and Enterprise is contact sales with no published price. Better Auth's framework has no user price, and Infrastructure Pro includes one SSO connection if you want their dashboard. Keycloak has no license line at any user count, so choose it only when someone will run the cluster. Downloads are on keycloak.org, and the cloud steps are on FusionAuth pricing.