Plan comparison · April 2026

Firebase Spark vs Blaze Plan: What's the Difference and When to Upgrade

The Blaze plan keeps all Spark free tier quotas and adds pay-as-you-go pricing for usage beyond those limits, plus features not available on Spark — Cloud Functions and phone authentication. You lose nothing by upgrading.

The one thing to understand: upgrading from Spark to Blaze does not remove or reduce your free tier quotas. All 50,000 daily Firestore reads, 20,000 daily writes, 5 GB Cloud Storage, and 360 GB hosting bandwidth remain free. You only pay for usage above those limits.

Full Spark vs Blaze Comparison Table

Service / Feature	Spark (Free)	Blaze — free quota retained	Blaze — price beyond free
Cloud Firestore reads	50,000 / day	50,000 / day	$0.06 / 100,000
Cloud Firestore writes	20,000 / day	20,000 / day	$0.18 / 100,000
Cloud Firestore deletes	20,000 / day	20,000 / day	$0.02 / 100,000
Firestore storage	1 GiB	1 GiB	$0.18 / GiB / month
Realtime Database storage	1 GB	1 GB	$5 / GB / month
Realtime Database download	10 GB / month	10 GB / month	$1 / GB
Cloud Storage	5 GB storage, 1 GB/day download	5 GB storage, 1 GB/day download	$0.026 / GB stored · $0.12 / GB download
Hosting bandwidth	360 GB / month	360 GB / month	$0.15 / GB
Hosting storage	10 GB	10 GB	$0.026 / GB
Cloud Functions	Not available	2M invocations free / month	$0.40 / 1M invocations
Phone / SMS Auth	Not available	10,000 verifications free / month	~$0.0046 / SMS (US); varies by country
Email/Social Auth	50,000 MAU	Unlimited	No charge at any volume
Anonymous Auth	Unlimited	Unlimited	No charge
Firebase ML	Free (cloud features limited)	Free on-device; Cloud Vision / Speech paid	Google Cloud API pricing
Remote Config	Unlimited	Unlimited	No charge
A/B Testing	Free	Free	No charge
Analytics	Unlimited (free forever)	Unlimited	No charge
Crashlytics	Unlimited	Unlimited	No charge
App Check	Free	Free	No charge
Network egress	10 GB / month	10 GB / month	$0.12 / GB

What You Gain by Upgrading to Blaze

Cloud Functions — unlocked entirely

Server-side logic, scheduled tasks (cron jobs), Firestore triggers, HTTP endpoints. Cloud Functions are the single most common reason developers upgrade. On Spark, functions simply don't run.

Phone / SMS authentication

Verify users by phone number. First 10,000 verifications per month are free on Blaze. Essential for apps that need mobile number verification or two-factor authentication.

Additional Google Cloud services

Access Cloud Vision AI, Speech-to-Text, Natural Language API, and the full GCP catalogue. All these require a billing account (Blaze).

Multiple Firestore databases

Spark limits you to one Firestore database per project. Blaze allows multiple databases — useful for multi-tenant architectures or separating production and test data.

Google Cloud credits (if eligible)

New Google Cloud accounts may qualify for $300 in free credits, applicable to Firebase services. Requires a billing account — which means Blaze.

Every Spark quota is preserved on the Blaze plan

You will not pay for usage that was previously free. The 50,000 daily Firestore reads, 20,000 daily writes, 5 GB Cloud Storage, and every other free tier limit stays exactly the same when you upgrade to Blaze. Upgrading does not change how free tier usage is counted. This is the most common misconception about Firebase billing.

When Should You Upgrade to Blaze?

Upgrade if any of these apply to your project:

You need Cloud Functions (server-side logic, triggers, scheduled tasks)

Your app needs phone/SMS authentication

You're approaching Spark quotas and don't want a hard cutoff mid-month

You want to connect Firebase to additional Google Cloud services

You're building for production (billing controls and budget alerts require Blaze)

You want access to multiple Firestore databases per project

When to Stay on the Spark Plan

You're building a prototype or MVP that doesn't need Cloud Functions

Your usage is comfortably within free tier limits and likely to stay there

You don't need phone/SMS authentication

You're not ready to add a payment method to the project

How to Upgrade to Blaze (Step by Step)

1

Open the Firebase console at console.firebase.google.com

2

Select your project, then click the gear icon → "Project settings"

3

Click "Usage and billing" in the sidebar

4

Click "Modify plan" next to your current Spark plan

5

Select "Blaze" and click "Continue"

6

Add a billing account or select an existing Google Cloud billing account

7

Set a budget alert immediately — enter an amount you're comfortable being notified at (e.g. $10 or $25)

Important: Budget alerts only notify — they don't cap spending. See the hidden costs guide for how to set up more protective controls.

Frequently Asked Questions

Does upgrading to Blaze cost anything upfront?

No. Upgrading from Spark to Blaze is free. You attach a billing account and agree to pay-as-you-go pricing, but your first billing period may be $0 if your usage stays within the same free tier quotas you had on Spark.

What happens if I hit Spark quotas without upgrading?

Can I downgrade back from Blaze to Spark?

How do I set a spending limit on the Blaze plan?

← Firebase Pricing Calculator Firestore Pricing →Cloud Functions Pricing →Hidden Costs Guide →