Convex vs Firebase
Convex and Firebase both answer the same question: where does your data live? A reactive backend where you write TypeScript functions instead of SQL, and queries push updates to clients automatically. Google's mobile-first backend with a document store, realtime sync, offline support and push notifications in one bundle. Convex bills against what you actually use, which is kind early and needs watching later; Firebase is more predictable and less forgiving of a quiet month.
Verdict
Convex bills against what you actually use, which is kind early and needs watching later; Firebase is more predictable and less forgiving of a quiet month.
Pick Convex if
- ✓Queries are reactive by default, so live-updating UI needs no subscription plumbing.
- ✓Backend functions are TypeScript sharing types with the frontend end to end.
- ✓Transactions and scheduling are built in, so background jobs need no extra service.
Pick Firebase if
- ✓Offline persistence and conflict handling on mobile are genuinely solved problems here.
- ✓Push notifications, crash reporting and analytics come from the same console.
- ✓Realtime listeners make collaborative and chat-style features straightforward.
| Comparison | Convex | Firebase |
|---|---|---|
| Pricing shape | Free tier for small projects, then a per-developer plan with usage-based function calls and storage. | Free Spark tier, then pay as you go priced mainly on document reads, writes and stored data. |
| Frameworks | Next.js, React Native, Expo | Next.js, React Native, Expo, Flutter |
| In one line | A reactive backend where you write TypeScript functions instead of SQL, and queries push updates to clients automatically. | Google's mobile-first backend with a document store, realtime sync, offline support and push notifications in one bundle. |
Pricing described qualitatively because published plans change often. Checked 2026-08-23. Confirm current terms on Convex and Firebase.
Convex
Strengths
- ✓Queries are reactive by default, so live-updating UI needs no subscription plumbing.
- ✓Backend functions are TypeScript sharing types with the frontend end to end.
- ✓Transactions and scheduling are built in, so background jobs need no extra service.
- ✓No separate API layer to write, since client calls functions directly.
Tradeoffs
- ✗Not SQL, so analytics tools and reporting stacks do not plug straight in.
- ✗The programming model is proprietary, making a later migration a rewrite.
- ✗Complex relational queries are more awkward than in a relational engine.
- ✗Smaller ecosystem, so fewer existing libraries assume Convex as the store.
Firebase
Strengths
- ✓Offline persistence and conflict handling on mobile are genuinely solved problems here.
- ✓Push notifications, crash reporting and analytics come from the same console.
- ✓Realtime listeners make collaborative and chat-style features straightforward.
- ✓Very long track record, so mobile developers already know the patterns.
Tradeoffs
- ✗Document model punishes relational data, pushing you toward heavy denormalization.
- ✗Billing counts document reads, so a careless listener can cost real money.
- ✗Security rules are a separate language with their own testing story.
- ✗Deep Google Cloud coupling makes leaving a full backend rewrite.
Frequently asked questions
Is Convex or Firebase better?
Neither is better in the abstract. Convex bills against what you actually use, which is kind early and needs watching later; Firebase is more predictable and less forgiving of a quiet month. Pick the one whose downside you can absorb, because both upsides are real.
What is the main drawback of Convex?
Not SQL, so analytics tools and reporting stacks do not plug straight in. The programming model is proprietary, making a later migration a rewrite.
What is the main drawback of Firebase?
Document model punishes relational data, pushing you toward heavy denormalization. Billing counts document reads, so a careless listener can cost real money.
Can you switch from one to the other later?
Usually, at a cost that grows with how much of your product leans on the database layer. Keep the integration behind a thin module of your own and the migration stays a weekend rather than a quarter.