Choosing an API is a long-term decision. Once you integrate, switching costs grow with every line of code, every user, and every day. Yet most developers choose APIs based on a 5-minute Google search and a blog post. Here's a systematic framework for evaluating APIs before you commit.
| Dimension | Weight | What to Check |
|---|
| Reliability | 25% | Uptime, SLA, incident history |
| Developer Experience | 20% | Docs, SDK quality, time to first call |
| Pricing | 20% | Model, transparency, growth costs |
| Performance | 15% | Latency, throughput, global coverage |
| Security | 10% | Auth methods, compliance, data handling |
| Longevity | 5% | Company stability, funding, market position |
| Flexibility | 5% | Lock-in, data portability, alternatives |
☐ Published uptime SLA (99.9%? 99.99%?)
☐ Status page history (last 12 months)
☐ Incident response time (how fast do they communicate?)
☐ Redundancy (multi-region? failover?)
☐ Rate limit behavior (429 response? queue? drop?)
open https://status.stripe.com/history
curl -o /dev/null -s -w "HTTP %{http_code} in %{time_total}s\n" \
https://api.example.com/v1/health
| Red Flag | What It Means |
|---|
| No status page | They don't track uptime (or don't want you to see it) |
| Multiple incidents/month | Reliability issues |
| >4 hour incident resolution | Slow response team |
| No SLA published | No uptime commitment |
| SLA with many exclusions | SLA is marketing, not a promise |
| Score | Criteria |
|---|
| 5 | 99.99%+ uptime, <15 min incident response, financial SLA |
| 4 | 99.95%+ uptime, <1 hour response, published SLA |
| 3 | 99.9%+ uptime, status page, reasonable track record |
| 2 | Some downtime issues, slow communication |
| 1 | Frequent outages, no status page, no SLA |
The single best evaluation: try to make your first API call in 5 minutes.
Timer starts when you land on the docs site.
☐ Find "Getting Started" (< 30 seconds)
☐ Create account / get API key (< 2 minutes)
☐ Install SDK (< 30 seconds)
☐ Make first successful API call (< 2 minutes)
☐ Understand the response (immediately clear)
Total: Should be < 5 minutes
| Check | Good | Bad |
|---|
| Code examples | Copy-paste, run, works | Pseudocode or outdated |
| Languages supported | Your language + 2 others | Only curl or only one language |
| Error documentation | Cause + solution for each error | Just error codes |
| Search | Full-text, relevant results | No search or broken search |
| Interactive explorer | Test endpoints in-browser | Static reference only |
import { APIClient } from 'api-sdk';
const client = new APIClient('sk_key');
const result = await client.resource.create({ name: 'test' });
const response = await fetch('https://api.example.com/v1/resource', {
method: 'POST',
headers: {
'Authorization': 'Bearer sk_key',
'Content-Type': 'application/json',
'X-API-Version': '2024-01-01',
'X-Request-Id': uuid(),
},
body: JSON.stringify({ name: 'test' }),
});
const data = await response.json();
☐ Pricing model (per-request, per-user, tiered, flat)
☐ Free tier (what's included, what's limited)
☐ Growth cost curve (what happens at 10x current usage?)
☐ Hidden costs (overage charges, premium features, support)
☐ Contract requirements (monthly vs annual, minimums)
| Usage Level | API Cost/Month | What to Watch |
|---|
| Prototype (100 calls/day) | Should be $0 (free tier) | Free tier limits |
| MVP (10K calls/day) | $0-50 | When free tier runs out |
| Growth (100K calls/day) | $50-500 | Per-unit cost at scale |
| Scale (1M calls/day) | $500-5,000 | Volume discounts available? |
| Enterprise (10M+ calls/day) | Custom | Need enterprise agreement? |
| Red Flag | Risk |
|---|
| "Contact sales for pricing" | Expensive, non-transparent |
| Overage charges without caps | Surprise bills |
| Features locked behind enterprise tier | Core features gated |
| Annual contract required for reasonable pricing | Lock-in |
| Price per "seat" for API access | Costs scale with team, not usage |
for i in {1..10}; do
curl -o /dev/null -s -w "%{time_total}\n" \
-H "Authorization: Bearer $API_KEY" \
https://api.example.com/v1/health
done
| Check | Good | Concern |
|---|
| P50 latency | <100ms | >200ms |
| P99 latency | <500ms | >1s |
| Global regions | 3+ regions | Single region |
| CDN/edge caching | Yes | No |
| Rate limits | Clear, documented | Undocumented or very low |
| Batch endpoints | Available | Every item requires separate call |
☐ HTTPS only (no HTTP option)
☐ API key scoping (read-only, write, admin)
☐ OAuth 2.0 support (for user-facing apps)
☐ IP allowlisting option
☐ Webhook signature verification
☐ SOC 2 compliance
☐ GDPR compliance (if EU users)
☐ Data encryption at rest
☐ Audit logs available
☐ Key rotation without downtime
| Score | Criteria |
|---|
| 5 | SOC 2 Type II, HIPAA, key scoping, IP allowlisting, audit logs |
| 4 | SOC 2 Type II, key scoping, webhook verification |
| 3 | HTTPS, API keys, basic security practices |
| 2 | HTTPS, but limited security features |
| 1 | Security concerns, no compliance certifications |
| Factor | Where to Find It |
|---|
| Funding | Crunchbase, press releases |
| Revenue growth | Job postings growth, public filings |
| Customer count | Case studies, press, G2 reviews |
| Engineering team size | LinkedIn, job postings |
| Open-source activity | GitHub commits, contributors |
| Community size | Discord/Slack members, forum activity |
| Red Flag | Risk |
|---|
| No funding and no revenue model | Company may shut down |
| Acqui-hire risk (small team, good tech) | API deprecated post-acquisition |
| Single person maintainer (OSS) | Bus factor = 1 |
| Pivoting frequently | API might not be core focus |
| Declining community activity | Losing developer mindshare |
☐ Can you export all your data?
☐ Is there a standard format/protocol? (REST, GraphQL, OpenAPI)
☐ Are there alternative providers?
☐ How much code would need to change to switch?
☐ Are there migration guides from/to competitors?
| Category | Lock-In Level | Why | Mitigation |
|---|
| Payments | High | Customer data, payment methods, subscriptions | Abstraction layer |
| Auth | High | User accounts, sessions, social connections | Standard protocols (OIDC) |
| Email | Low | SMTP is standard, easy to switch | Use SMTP abstraction |
| Search | Medium | Index configuration, relevance tuning | Standard query syntax |
| Storage | Low | S3 API is a standard | S3-compatible providers |
| AI/LLM | Low | OpenAI format is becoming standard | AI gateway |
| Analytics | Medium | Historical data, dashboards, team training | Export + parallel run |
## API Evaluation: [API Name]
| Dimension | Score (1-5) | Weight | Weighted |
|-----------|------------|--------|----------|
| Reliability | _/5 | 25% | _ |
| Developer Experience | _/5 | 20% | _ |
| Pricing | _/5 | 20% | _ |
| Performance | _/5 | 15% | _ |
| Security | _/5 | 10% | _ |
| Longevity | _/5 | 5% | _ |
| Flexibility | _/5 | 5% | _ |
| **Total** | | 100% | **_/5** |
### Notes
- Strengths:
- Weaknesses:
- Deal-breakers:
- Recommendation: Use / Don't use / Evaluate further
| Total Score | Recommendation |
|---|
| 4.5-5.0 | Strong adopt — integrate confidently |
| 3.5-4.4 | Adopt — good choice with minor concerns |
| 2.5-3.4 | Consider — evaluate alternatives |
| 1.5-2.4 | Avoid — significant concerns |
| 1.0-1.4 | Do not use — fundamental issues |
If you don't have time for the full framework:
1. (5 min) Read the landing page — clear value proposition?
2. (5 min) Try the 5-minute test — working API call?
3. (5 min) Check pricing page — transparent? Affordable at 10x?
4. (5 min) Check status page — uptime history?
5. (5 min) Search "[API name] alternatives" — what do others say?
6. (5 min) Check GitHub/Discord — active community?
If any step fails or raises concerns → full evaluation needed
| Mistake | Impact | Fix |
|---|
| Choosing based on free tier alone | Locked into expensive growth pricing | Project costs at 10x current usage |
| Not testing from production region | Latency surprises in production | Test from your actual deployment region |
| Ignoring error handling | Painful debugging in production | Test error cases during evaluation |
| Not reading the SLA | No recourse during outages | Read SLA before signing |
| Skipping the "how do I leave?" question | Expensive migration later | Assess lock-in before committing |
| Only evaluating happy path | Missing edge cases | Test webhooks, rate limits, error responses |
Evaluate APIs systematically on APIScout — side-by-side comparisons with reliability scores, DX ratings, and pricing breakdowns.
