Bottom line: Kiro is AWS’s agentic coding IDE, and its free tier is permanent: 50 credits a month, every month, with access to open-weight models and Claude Sonnet 4.5 within limits. That is enough to run real spec-driven features on a small project — not enough for all-day agent work. If you like the idea of an AI that writes requirements, design, and a task list before it writes code, Kiro Free is the cheapest way to try that workflow properly.
What is Kiro?
Kiro is an agentic AI development environment from Amazon Web Services. It comes as a desktop IDE (built on Code OSS, so you can import VS Code settings, themes, and compatible extensions), a CLI, a web interface, a mobile app, and Kiro Crew, an open-source workspace that runs on your own machine. Its signature idea is spec-driven development: instead of jumping straight to code, Kiro works with you to define requirements, a system design, and an ordered task list first, then implements against that spec. It also supports agent hooks, steering files that carry your project rules across sessions, and parallel agents for larger codebases.
What is actually free with Kiro?
- A perpetual free tier with 50 credits a month — Kiro’s own FAQ calls it “perpetual,” and unused plan credits reset each month rather than rolling over.
- Access to open-weight models and Claude Sonnet 4.5, with limits, on the free tier.
- The full spec-driven workflow: specs, steering, hooks, and agent execution in the IDE, CLI, and web surfaces.
- Support for a long language list, including Python, Java, JavaScript, TypeScript, C#, Go, Rust, PHP, Ruby, and Kotlin.
- Kiro Crew, the open-source local workspace, is free to install from GitHub.
How far do 50 credits actually go?
A credit is Kiro’s unit of work per prompt. Simple prompts can cost less than 1 credit; a complex spec task typically costs more than 1, and the model changes the rate — a task costing X credits via Kiro’s Auto router costs 1.3X via Sonnet 4.6. So 50 credits buys a handful of properly spec’d features or a few dozen small asks a month, not a full-time pair programmer. Paid tiers raise that ceiling — Pro $20/month, Pro+ $40/month, Pro Max $100/month, Power $200/month — and paid plans can buy add-on credits at $0.04 each. Free users cannot buy add-ons: when the 50 are gone, you wait for the reset.
What is the catch?
Two honest ones. First, the credit meter makes heavy agent sessions feel rationed; developers used to flat-rate autocomplete will notice it. Second, privacy: Kiro’s FAQ says content from free-tier users who sign in with a social login or Builder ID may be used for service improvement, with an opt-out available in the documentation. Paid users signing in through IAM Identity Center are not collected from. Read the setting and flip the opt-out if that matters to you. The free tier is also not available in AWS GovCloud.
Pros and cons
Pros
- A genuinely permanent free tier — 50 credits a month, not a 14-day trial.
- Specs before code: requirements, design, and tasks are documented, which makes agent work reviewable.
- Frontier model access on free, including Claude Sonnet 4.5 within limits.
- IDE, CLI, web, and mobile surfaces share steering and configuration.
Cons
- 50 credits a month runs out fast on large, multi-file tasks.
- Free users cannot buy add-on credits to top up.
- Free-tier content may be used for service improvement unless you opt out.
- The spec-first workflow can feel heavy for a one-line fix.
Who is Kiro best for?
Kiro’s free tier is best for developers building features that are big enough to plan: students and hobbyists shipping side projects, engineers on AWS-heavy teams evaluating spec-driven development, and anyone who has watched a coding agent wander off-plan and wants the plan written down first.
FAQ
Is Kiro really free?
Yes. Kiro has a perpetual free tier with 50 credits a month, according to Kiro’s official FAQ. It is not a time-limited trial.
What models can free users access?
Open-weight models and Claude Sonnet 4.5, with limits. Paid tiers widen model access and raise credit allowances.
Do unused Kiro credits roll over?
No. Plan credits reset at the start of each billing month. Purchased add-on credits on paid plans are separate and expire 12 months after purchase.
Do I need an AWS account for Kiro?
No. You can sign in with GitHub, Google, or an AWS Builder ID instead.
Research-based review: pricing, credit, and privacy details checked against Kiro’s official FAQ in October 2026. No hands-on testing is claimed.