StackSays
Menu

Authentication · decision tool

Clerk vs Auth0 — startup DX or enterprise checklist?

Clerk bills per retained user; Auth0 bills in tier jumps after a generous free 25K. Your MAU curve and enterprise needs decide — set them and see.

Prices verified 2026-07-15 against official pricing pages · fit weights are our estimates (see methodology) · share the URL to share your configuration

As of Jul 2026, with 5,000 monthly active users, a $100 budget for this slot, Clerk ranks first for these inputs at 96% fit and a StackSays-estimated $0/month (Auth0: 96% fit, $0/month). Fit weights are our estimates; prices trace to official pages. Change any input below and the verdict recomputes.

Your situation

The verdict updates as you move these.

Toss-up — your priorities decide, not the tools

Clerkfit 96% · est $0/mo

Plug-and-play auth with the best prebuilt UI; you pay for the polish as you grow

vs Auth0: fit 96% against 96%, est $0 against $0 per month — genuinely close; read both risk lists below

Clerkfit 96%
$0/mo
Auth0fit 96%
$0/mo

Comparing 2 tools head-to-head. Open the full field (7 options) →

The decision, in plain words

For a team of 2 at 5,000 monthly active users and a $100.00/mo budget for the auth provider slot, Clerk leads at 96% fit and $0/mo. The two rules doing the work: budget fit (Runs free at your usage — $0 vs your $100/mo budget); batteries included (Bundles prebuilt sign-in UI, organizations/teams, enterprise SSO — fewer services to glue at team size 2).

Auth0 is a genuine coin-flip here (96% fit, $0/mo) — read both risk lists and pick the failure mode you prefer.

Honest weak spot of the pick: hosted user store — migrating away means a coordinated export (password hashes via support).

Generated from the calculation above — every number traces to the sourced data; nothing here is written by an AI making things up.

Why Clerk scores 96%

Budget fit (weight 30, our estimate) — Runs free at your usage — $0 vs your $100/mo budget+30
Batteries included (weight 12, our estimate) — Bundles prebuilt sign-in UI, organizations/teams, enterprise SSO — fewer services to glue at team size 2+12
Exit cost (weight 4, our estimate) — Hosted user store — migrating away means a coordinated export (password hashes via support)-1.2
Ecosystem maturity (weight 8, our estimate) — established — our estimate from ecosystem age, docs and hiring pool+8
Free-tier runway (weight 10, our estimate) — Your usage fits the free tier today (50,000 monthly retained users (MRU), full features)+10
Total (lines sum exactly)58.8
Possible range −64…+64 (sum of active rule weights) · fit % = (total + max) / (2 × max)(58.8 + 64) / 128 = 96%

How the $0/mo estimate is calculated

Your usage fits Clerk's free tier (50,000 monthly retained users (MRU), full features) — the estimate is $0.

What could change this verdict

No single input change within the tested range changes the winner.

Cost risk

Estimated now (StackSays estimate, not your final bill)$0/mo · Free tier
Free-tier statusOn the free tier (50,000 monthly retained users (MRU), full features)
Next known billing thresholdFree tier caps at 50,000 mau — beyond that you change plans

Official prices verified 2026-07-15; calculation is deterministic code over those prices.

At a glance

ToolFree tierPaid entryVerified
Clerk50,000 monthly retained users (MRU), full featuresPro $25/mo2026-07-15
Auth025,000 MAU, no credit cardEssentials $35/mo2026-07-15
Where did you land?anonymous, one click

Data sources

ToolSourceVerified
ClerkClerk pricing page2026-07-15
Auth0Auth0 pricing page2026-07-15

A monitor re-checks these pages for changes; when a vendor moves a price, the date updates and every verdict recomputes.

People also ask

Can I use Clerk for free?

Yes — up to 50,000 monthly retained users with full features (verified 2026-07-15). Note the metric: Clerk counts retained users (MRU), not raw MAU. The Pro plan is $25/mo and adds $0.02 per user beyond 50K — at 100K users that's ~$1,025/mo.

Can I use Auth0 for free?

Yes — the free tier covers 25,000 MAU with no credit card (verified 2026-07-15). The catch is what comes after: paid plans start at $35/mo for only 500 MAU and bill in tier jumps, so crossing the free ceiling is a real cliff.

Keep deciding