Firebase Cost Calculator for 2026: Spark vs. Blaze
Estimate monthly Firestore, Realtime Database, Cloud Functions, and storage costs from an Android or Kotlin app workload, then compare Spark and Blaze.
Kotlin does not carry a Firebase pricing premium. Reads, writes, listeners, functions, stored data, downloads, authentication methods, and region determine the bill.
Spark vs. Blaze in 60 seconds
| Plan detail | Spark | Blaze |
|---|---|---|
| Billing account | No payment method required | Links the project to Cloud Billing |
| Usage above no-cost quotas | Products are limited or unavailable after their quotas | Eligible no-cost quotas remain, then overage is pay as you go |
| Cloud Functions | Deployment is unavailable | Required for deployment; eligible no-cost compute quotas can still apply |
| Cloud Storage for Firebase | Unavailable | Required since February 3, 2026; bucket and region affect rates |
Model an Android app workload
Choose a starting profile or enter your own average daily usage. The model assumes roughly uniform daily activity across a 30-day month.
The checkboxes affect plan guidance but not the dollar total. Cloud Storage depends on bucket type, region, operations, and destination. Phone-auth rates depend on destination country.
Modeled monthly Firebase cost
Change an input to update the estimate.
| Line item | Modeled usage | Cost |
|---|---|---|
| Estimated total | $0.00 | |
Included: Firestore reads, writes, deletes, storage; Realtime Database storage and downloads; 1st-gen Cloud Functions invocation count. Excluded: Firestore egress and index-entry amplification, Functions compute/networking/deployment, Cloud Storage, phone/SMS, Hosting, Identity Platform, taxes, and third-party APIs.
What this calculator assumes
| Firestore location | Reads / 100K | Writes / 100K | Deletes / 100K | Storage / GiB-month |
|---|---|---|---|---|
| North America multi-region (nam5) | $0.06 | $0.18 | $0.02 | $0.18 |
| Iowa regional (us-central1) | $0.03 | $0.09 | $0.01 | Approximately $0.15 |
The eligible default Firestore database receives 50,000 reads/day, 20,000 writes/day, 20,000 deletes/day, 1 GiB stored data, and 10 GiB outbound transfer per month at no cost. Additional or named databases do not receive that free quota.
Realtime Database includes 1 GB stored and 10 GB downloaded per month, then uses $5/GB-month for storage and $1/GB downloaded. The Functions line models 1st-gen, Tier-1 invocations only: the first 2 million invocations per month are no cost, then $0.40 per million. Compute and networking can add charges.
Android patterns that raise Firebase usage
- Snapshot listeners that return large result sets or reconnect frequently
- Repeated reads caused by screen refreshes, pagination mistakes, or missing caching
- Security rules that perform additional document reads
- Function triggers that fan out into more reads, writes, or external calls
- Media-heavy workflows that shift cost toward Cloud Storage and transfer
- Phone authentication, whose SMS rates vary by destination country
Cloud Storage changed in 2026
Since February 3, 2026, Cloud Storage for Firebase requires the Blaze plan.
No-cost usage can still apply, but legacy *.appspot.com buckets and
newer *.firebasestorage.app buckets use different quotas and rates.
That variability is why this simplified Android estimator flags Storage as a Blaze requirement without adding a generic Storage dollar amount. Use the live Google pricing table for the bucket and region you actually deploy.
Pricing sources, assumptions, and last review
Last verified July 12, 2026 against Google’s Firebase pricing table and product-specific billing documentation. Results exclude software-development labor; this page estimates selected backend usage only.
Firebase pricing questions
Is Firebase free in 2026?
Firebase can cost $0 when a project stays within no-cost products and usage quotas. Spark is the no-cost plan. Blaze is pay as you go and retains eligible no-cost usage before additional charges begin.
Does Firebase cost more for Kotlin or Android apps?
No separate Kotlin or Android premium applies. The bill depends on Firebase products and measured usage. Android implementation choices can change that usage.
What drives Cloud Firestore costs?
Firestore bills document and index-entry reads, writes, deletes, stored data, and network transfer. Realtime listeners can generate reads as results change or clients reconnect.
Do Firebase budget alerts stop charges?
No. Budget alerts notify billing-account owners but do not cap usage or charges. Use quotas, architecture controls, monitoring, and tested failure behavior as well.
Which calculator should I use?
Use this page to translate Android usage patterns into a first-pass estimate. Use the advanced raw-usage calculator when you know exact Firestore, Realtime Database, and Functions volumes. Use the scenario planner to compare architecture and growth patterns.
Need the exact raw-usage model?
Move from per-user assumptions to direct Firestore, Realtime Database, and Cloud Functions inputs.
Open the advanced Firebase calculator Get help with Firebase app architecture