True cost comparison — not just what the pricing page says
Quick Verdict
Grammarly saves you 5%
Best for Grammarly
AI writing assistant for grammar, clarity, and tone. Free plan is basic, then $12-$15/user/mo for fu
Best for Postman
API development and testing platform. Free for individuals, then $14-$49/user/mo for teams — but col
AI writing assistant for grammar, clarity, and tone. Free plan is basic, then $1...
Advertised
$0
/month
True Cost
$12
/month (typical)
AI Writing Assistance Limits
Generative AI features (rewrite, compose, ideate) have monthly prompt limits. Premium gets 1,000 pro...
Premium Required for Full Features
Free plan only catches basic grammar and spelling. Clarity, tone detection, word choice, formality l...
Per-Seat Team Pricing
Grammarly Business at $15/user/mo. A 50-person team = $750/mo ($9,000/yr). Team analytics, style gui...
API development and testing platform. Free for individuals, then $14-$49/user/mo...
Advertised
$0
/month
True Cost
$48
/month (typical)
Collection Runner Hard Limit
Free: 25 runs/mo. Basic: 250 runs/mo. Professional: 2,500 runs/mo. CI/CD pipelines running tests on ...
Monitoring Call Overages
API monitoring calls capped per plan. Exceeding limits requires purchasing additional monitoring blo...
Mock Server Call Limits
Mock server calls capped at 1K (free), 10K (Basic), 100K (Professional). API-first development with ...
Grammarly advertises $0/mo. Postman advertises $0/mo.
Grammarly has 3 documented hidden fees. Postman has 3.
Grammarly confidence: 76%. Postman confidence: 72%.
| Metric | Grammarly | Postman | Winner |
|---|---|---|---|
| Advertised Price | $0/mo | $0/mo | Grammarly |
| True Monthly Cost | $12/mo | $48/mo | Grammarly |
| Hidden Fee Total | +$12/mo | +$48/mo | Grammarly |
| # Hidden Fees | 3 | 3 | Grammarly |
| Confidence Score | 76% | 72% | Grammarly |
| Pricing Tiers | 3 | 4 | — |
| Affiliate Program | None | None | — |
Grammarly advertises $0/mo and Postman advertises $0/mo. However, when you include hidden fees, Grammarly has 3 documented hidden fees adding +$12/mo, while Postman has 3 hidden fees adding +$48/mo. Based on true cost, Grammarly is typically 5% cheaper.
Grammarly has 3 documented hidden fees: AI Writing Assistance Limits, Premium Required for Full Features, Per-Seat Team Pricing. These add approximately +$12/mo on top of the $0/mo advertised price.
Postman has 3 documented hidden fees: Collection Runner Hard Limit, Monitoring Call Overages, Mock Server Call Limits. These add approximately +$48/mo on top of the $0/mo advertised price.
Choose Grammarly if: AI writing assistant for grammar, clarity, and tone. Free plan is basic, then $12-$15/user/mo for fu. Choose Postman if: API development and testing platform. Free for individuals, then $14-$49/user/mo for teams — but col. The right choice depends on your team size, usage volume, and which features you need most.
This comparison is based on manual research of official pricing pages, terms of service, and user reports. Grammarly data has a 76% confidence score and Postman has 72%. Prices were last verified in April 2026. For the most accurate estimate, enter your specific usage in our calculator.
Enter your usage to see personalized pricing for both tools
Use Free Calculator