Published 2026-06-02 · reference prices, verify before budgeting
"Free tier" means very different things. Some are perpetual, some are trial credits that expire. Here are the ones genuinely worth building on.
Google Gemini (AI Studio) is the standout — a real, rate-limited free tier with no credit card. OpenAI and Anthropic give expiring trial credits only.
SendGrid: 100/day forever. Resend: ~3,000/month. Plenty for a small app's transactional mail.
CoinGecko Demo tier (free key) covers most hobby dashboards; exchange APIs like Binance are free for tickers.
Google Maps gives a monthly free allowance per product (billing still required); OpenStreetMap + Leaflet is fully free. SerpAPI offers ~100 searches/month free.
Free tiers are for building and low volume. Before you ship something popular, model the paid cost — a feature that's free at 100 calls/day can be expensive at 100,000. The cost calculator helps for AI; for the rest, multiply your expected volume by the per-unit price and don't get surprised.
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Reference estimates. Not affiliated with any provider.