OpenAI API vs Loops
Frontier models: GPT-5, o-series reasoning, image, audio, embeddings
vs. Email marketing for SaaS — loops, transactional, campaigns in one
Pricing tiers
OpenAI API
Free Tier (Trial)
$5 free credit for new accounts. Rate-limited.
Free
Pay-as-you-go
No monthly min. Per-token pricing by model.
$0 base (usage-based)
Usage Tiers (1-5)
Automatic tier promotion based on cumulative spend. Higher tiers = higher rate limits + new model access.
$0 base (usage-based)
Enterprise
Custom. Priority access, SLA, dedicated capacity.
Custom
Loops
Free
1,000 subscribed contacts. 4,000 sends/month. All features. Loops footer on emails.
Free
Paid — 1.5k
1,500 contacts. Unlimited sends. No footer.
$15/mo
Paid — 5k
5,000 contacts. Unlimited sends.
$49/mo
Paid — 10k
10,000 contacts.
$99/mo
Paid — 25k
25,000 contacts.
$199/mo
Paid — 50k
50,000 contacts.
$349/mo
Custom
>100k contacts — contact sales.
Custom
Free-tier quotas head-to-head
Comparing free-tier on OpenAI API vs free on Loops.
| Metric | OpenAI API | Loops |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
OpenAI API · 12 features
- Assistants API — Stateful assistants with tools, threads, file search.
- Batch API — 50% discount for async processing within 24h.
- Chat Completions API — Classic /v1/chat/completions endpoint.
- Files API — Upload docs for retrieval, fine-tuning, batch.
- Fine-Tuning — Supervised + DPO fine-tuning for GPT-4o, GPT-4.1, GPT-4o-mini.
- Function Calling — JSON-schema tool calling; parallel calls supported.
- Moderation — Safety classifier API (free).
- Prompt Caching — Auto-cache repeated prefixes; 50% cheaper cached hits.
- Realtime API — WebSocket streaming voice + text with low latency.
- Responses API — Stateful conversational API.
- Structured Outputs — Enforced JSON schema compliance.
- Vision — Image input for GPT models.
Loops · 12 features
- API Keys — Scoped keys for testing vs production.
- Audiences (Segments) — Filter contacts by properties + event behavior.
- Campaign Analytics — Open/click/unsubscribe rates, heatmaps, A/B significance.
- Campaigns — One-off broadcasts to audience segments. Schedule + A/B test subject.
- Contacts — Contact records with custom properties (strings, numbers, booleans, dates).
- Email Editor — Visual block-based + Markdown + HTML modes.
- Events — Send events to trigger loops/journeys or filter audiences.
- Loops (Automations) — Event-triggered automation flows with delays + conditions.
- Mailing Lists — Opt-in lists with subscribe/unsubscribe preferences per list.
- Template Library — Pre-built templates for SaaS use cases (onboarding, digest, launch).
- Transactional API — Send transactional emails (receipts, password resets) via /transactional endpoin…
- Webhooks — Subscribe to contact/event changes.
Developer interfaces
| Kind | OpenAI API | Loops |
|---|---|---|
| SDK | openai-dotnet, openai-go, openai-node, openai-python | @loops/loops, loops-py |
| REST | OpenAI REST API | Loops REST API |
| MCP | OpenAI MCP | — |
| OTHER | Realtime API (WebSocket) | Webhooks |
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